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[Display omitted] • Green chemical reactions by substituting resorcinol with the natural bio-phenolic compound tannin. • Synthesis of a new sustainable Carbon Kraft. • Methodology to reuse Kraft liquor in a circular economy. • A sustainable composite radome design for unmanned aerial vehicles (UAV). • Electromagnetic design of transparent materials through impedance match theory. The study addresses environmental and commercial challenges posed by weak black liquor (WBL) generated through the Kraft process in the paper industry. WBL, a toxic waste, annually reaches a staggering 1.3 billion tonnes globally. Currently, it is either incinerated for energy production or subjected to costly and complex chemical treatments to extract valuable compounds. Despite efforts to develop a scalable value-added material, the existing methods are inefficient in fully reusing WBL. Here, we report a simple chemical synthesis process that reuses 100 % of WBL without generating any waste materials; even salts recovered during the process might be reintegrated into the industry as chemical byproducts. Furthermore, given the simplicity and efficiency of the proposed synthesis methodology to transform WBL into a novel and sustainable porous carbon material, the carbon Kraft (CK). The process can also be scaled by using the right synthesis proportions and within a circular economy. CK exhibited desirable characteristics with a renewable content of 65 wt%, including a turbostratic graphitic-like structure (48.8 % graphitized), carbon content of 85 wt%, large specific surface area of 234.0 m2∙g−1, nanoporosity of 0.13 cm3∙g−1, and density of 1.92 g∙(cm3)-1. Moreover, CK showed electrical and thermal insulating characteristics, essential for use as fillers for elastomeric composite in electromagnetic transparent radome structures used to protect antennas and radars of unmanned aerial vehicles (UAV) from harsh environmental effects. Radomes were designed through the electromagnetic impedance match theory of half-wavelength calculations over specific frequencies of 1.3, 10, 15, 20, and 30 GHz. Results showed excellent transmission loss between −0.41 and −1.48 dB, representing 90.8 % and 70.5 % of transmittance, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • It provides practical aspects of laser processing to achieve graphene materials. • It covers latest research on direct laser carbonization/graphitization of polymers. • Focusing on one laser processing operation: carbonization/graphitization. • Carbonization can occur at low temperature, unlike high-temperature graphitization. • Beam intensity profile characteristics of lasers are very crucial for processing. In recent years, laser-induced graphene (LIG) and laser-scribed graphene (LSG) have emerged as highly effective methods for graphene fabrication, offering precise control over patterned geometries. These laser-based approaches provide direct synthesis of graphene without the need for catalysts, enabling high-precision patterning of materials with enhanced properties, making ideal components for flexible electronic devices. The procedures show good potential for reduced synthesis costs when compared to alternative methods. This review presents an overview of the latest advancements in direct LIG/LSG formation from carbonaceous precursors, with a specific focus on nanostructured electrode patterning for energy storage (such as supercapacitors (SCs) and batteries) and sensing (including electrochemical sensors and biosensors). A diverse array of lasers has been employed to irradiate various substrates, including polymers like polyimide (PI) and polydimethylsiloxane (PDMS), as well as biodegradable and edible materials such as wood, leaves, clothes, paper, and food, to directly generate graphene patterns. Key aspects addressed in this review include electrode designs, laser processing parameters, reduction and growth mechanisms, precursor materials, and processing atmospheres. Finally, the review outlines the main challenges encountered and discusses some of the most promising future directions in LIG/LSG and their application in energy storage and sensing devices. This comprehensive overview aims to shed light on the ongoing advancements and potential breakthroughs in this rapidly evolving field. [ABSTRACT FROM AUTHOR]

[Display omitted] • The advanced sensing and energy conversion for wood-based composites were constructed. • Establish the relationships on interfacial adhesion-carbonization-electron transport processes. • A favorable permeation can promote better interfacial adhesion. • Excellent interfacial adhesion contributes to the formation of a continuous char-layer network. • Highly graphitized char-layer network facilitates rapid electron transport. With the low carbon-driven development of modern intelligent, research towards novel materials is concentrating on the sustainable biomass-based advanced functional composites. The advanced functionalized wood toward sensing, optoelectronic devices, and energy conversion has been contributed to fast electron transport upon temperature or photo stimulus. Fast electron transport has been highly depended on the interfacial adhesion between the functional layer and wood matrix as well as graphitization degree during carbonization, which promote the electronic excitation and jumps. Here, we develop wood-based functional composites for advanced fire warning and energy conversion by loading metal–insulator transition (MIT) function factor (Ti 3 O 5) onto different woods via liquid crosslinkers, and systematically establish the interfacial adhesion-carbonization-electron transport processes and their relationships on the sensing and photothermal conversion properties. Firstly, balsa with high porosity (pore diameter ≈50 μm), low density (0.16 g/cm3) and extractives content (total extractives content 16.27 %) facilitates crosslinker penetration due to the more holding space and lower nonpolar components. A favorable permeation can promote better interfacial adhesion, and the formation of a continuous conductive network of char-layers during carbonization. Secondly, the crosslinker (chitosan) with excellent adhesion (1 level) and char-forming ability (char residues is 21.7 %), facilitates the formation of a compact network of highly graphitized char-layers (I D /I G =0.81), which increases the electrical conductivity (highest conductivity 5.52 × 10-4 S/m). We found that the most sensitive flame trigger time (0.86 s) for fire warning and the highest evaporation flux (1.63 kg m-2h−1) for desalination can be obtained by using balsa which coupled the chitosan as well as the Ti 3 O 5. [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalytic pyrolysis significantly reduces the graphenization temperature of biomass. • Metal carbides are crucial intermediate phases during graphenization. • Hydrothermal pre-treatment allows an energy saving of 85% in pyrolysis. • Fast solar pyrolysis promotes graphene layers growth and flattening in biocarbon. • Energy assessment highlights significant energy savings of graphenization processes. Reducing energy consumption and environmental impact in the graphenic material production is of foremost importance. While using lignocellulosic biomass is gaining momentum, processing such a non-graphitizable resource is energy consuming as it requires a thermal treatment above 2000 °C. Three alternative carbonization routes are analyzed: catalytic, hydrothermal pre-treatment and solar. We discuss the sustainability of the biocarbon production as compared to conventional high temperature biomass carbonization. The mechanisms of carbonization and graphenization is unveiled using a variety of characterization methods from macroscopic to nanoscopic scale. In catalytic graphenization, it is showed that metal carbides play a crucial role as intermediate phases in the graphenization mechanism. Solar-driven pyrolysis focused intense radiative flux resulting in an improve of the growth and flattening of graphene layers in biocarbon. For each process considered, the operating conditions can finely be tuned to control the graphenization degree, and successfully convert non-graphitizable lignocellulosic biomass into graphenic biocarbon. This review provides new insights on mechanisms in relation to the energy and environmental assessment. For calcium-doped biomass we estimate an energy saving of 22 % when working at 1600 °C compared to carbonization of raw biomass at 2000 °C attributed to the formation of calcium carbide around 1300 °C. Hydrothermal pre-treatment provides a carbon pre-structuration which could save up to 85 % of pyrolysis energy input by lowering the graphenization temperature to 1200 °C, while solar pyrolysis consumes half the energy as compared to the conventional one. This drastically reduces the environmental impact of the biocarbon production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow structure enhances the wave absorption properties significantly. • The addition of TiO 2 and Fe 3 C improve the impedance matching characteristic. • Various loss mechanism like dielectric, magnetic, multiple reflection loss. • Strong absorption intensity and broad bandwidth at low mix ratio and thin thickness. In order to face the challenge of achieving high-efficiency and lightweight wave absorption materials, we prepared the poly-m-phenylene isophthalamide (PMIA)/TiO 2 /Fe 3 C (PTF) composites with hollow structure by coaxial electrospinning and carbonization process. PMIA as the carbon source provided a three-dimensional (3D) conductive network, using TiO 2 and Fe 3 C to improve the impedance matching, reinforce the hollow structure, and increase the absorption mechanism of composites. Significantly, the minimum reflection loss (RL min) value of optimal material is −58.1 dB at 14.88 GHz and the effective absorption bandwidth (EAB) of 6 GHz with the matching thickness of 2.3 mm, and the filling content is only 13 wt%. The excellent absorption property is maintained even after heating, immersing, and long-term use. This work provides the reference of hollow carbon nanofiber absorbers with excellent comprehensive properties and has more powerful practicability in a variety of environmental conditions. [ABSTRACT FROM AUTHOR]

This study employs a simple laser-induced carbonization strategy to convert commercial polypropylene and bamboo into an efficient bilayer evaporator. [Display omitted] • A mechanism for the laser-induced carbonization of polypropylene has been proposed. • Highly controllable laser-induced carbonized material (LIC) has been achieved. • The bamboo/LIC double-layer solar evaporator exhibits excellent performance. Solar water evaporation technology is of great significance in alleviating the problem of clean water shortage. However, interface evaporation materials are crucial for solar evaporator and are hindered by high costs, complex processes, and environmental issues. In this work, a simple, fast, and environmentally friendly laser-induced carbonization strategy was used to convert commercial polypropylene into porous carbon materials in a one-step process, and assembled with natural bamboo to form an efficient dual-layer evaporator. The residual carbon nanotubes catalyst in the carbonized products further enhance its evaporation performance. The water evaporation rate of the evaporator under one sun is 1.93 kg·m−2·h−1. In addition, the evaporator has an evaporation rate of 1.62 to 1.85 kg·m−2·h−1 for wastewater containing methylene blue, carmine, CuCl 2 and FeCl 3. This strategy not only overcomes the limitations of traditional polymer carbonization methods but also allows for size adjustment based on the quantity of bamboo, and has been successfully applied to wastewater evaporation experiments under cold outdoor weather conditions. The proposed strategy not only elucidates the carbonization mechanism of polymers under laser irradiation, but also provides a new approach for the field of solar water evaporation. [ABSTRACT FROM AUTHOR]

• A systematic method for the comprehensive utilization of RAP is proposed, the separated aggregate can be reused for road construction. • Porous structure and C-O groups are formed after the oxygen-enriched waste asphalt carbonization. • The waste asphalt derived carbon exhibits a specific capacity of 645.1 mAh/g at 0.1 A/g current density, while the capacity remains 96.8% after 800 cycles at 0.2 A/g. • The effects of C-O structure formed after oxygen incorporation were investigated by DFT calculation. The current recycling efficiency of recycled asphalt pavement (RAP) remains low, leading to significant non-renewable resource wastage. Herein, we proposed a method for utilizing RAP based on the aging characteristics of waste asphalt, which separates RAP into two parts: waste asphalt and aggregate. The separated aggregate can be reused for road construction, and the separated asphalt is converted into the negative electrode material of lithium-ion battery after oxygen enrichment treatment and carbonization. In the process of carbonization, the waste asphalt formed a three-dimensional porous carbon structure and C-O configuration suitable for lithium storage under the effect of oxygen elements. This carbon material exhibits a specific capacity of ∼ 645 mAh g–1 at 0.1 A g–1 current density, while the capacity remains ∼ 97 % after 800 cycles at 0.2 A g–1. The DFT calculation results demonstrate the enhanced adsorption of Li-ion near the C-O configuration, which further proves the beneficial effect of oxygen incorporation. By efficiently separating aggregate from waste asphalt, this study explores favorable conditions for waste asphalt utilization, enhances RAP reuse efficiency, and provides dual benefits in terms of energy conservation and environmental protection. [ABSTRACT FROM AUTHOR]

• Easily available coir fibers were supplied for the production of evaporators. • Carbon nanoparticles coating on coir fibers enabled the photo-thermal conversion. • Carbon-coated coir fibers were woven into units for assembling array evaporators. • Tree-like multidirectional water transportation was realized by the array design. • The highest evaporation rate of 4.19 kg m-2h−1 was achieved by the evaporator. Coconut husk as a raw material for the production of solar water evaporators has received considerable attention due to its abundance and availability. However, common treatment methods such as carbonization applied to capacitate the coconut husks for photothermal conversion were not favor for realizing rapid evaporation, as they failed to exploit the original structure of coconut husks. Herein, coir fibers extracted from the coconut husks were directly supplied to the production of functionalized evaporators with carbon nanoparticle coating, which preserved the pristine structure of coir fibers and allowed them to rapidly transport water in multiple directions like trees. These fibers were further assembled into array evaporators to maximize their exposed surface area for efficient evaporation. As a result, the carbon-coated coir fiber array evaporator prepared in the present work showed the highest evaporation rate of 4.19 kg m-2h−1 during solar water evaporation experiments under 1.0 sun illumination. Our work presents an approach for achieving effective solar water evaporation based on carbon-coated coir fiber array evaporator with large exposed surface area and tree-inspired multidirectional fast water transportation. [ABSTRACT FROM AUTHOR]

[Display omitted] • PET-derived porous carbons were developed using autogenic pressure carbonization. • The highest CO 2 uptake achieved at 25 °C and 101.3 kPa was 4.44 mol/kg. • The environmental effect of porous carbon materials was evaluated using life cycle assessment. Plastic waste is a significant environmental concern worldwide because it harms wildlife, pollutes the environment, and poses a risk to human health. Upcycling plastic waste into porous carbon for CO 2 capture is regarded as a promising solution to address plastic pollution and global warming. In this study, a novel synthesis method involving autogenic pressure carbonization and KOH activation was developed to prepare polyethylene terephthalate (PET) waste-derived porous carbon. Autogenic pressure carbonization is a simple process that can efficiently convert carbon precursors into pyrolytic carbon, in which the decomposition products of carbon precursors are confined in a closed reactor and undergo a series of secondary reactions without being removed. In this study, two distinct methods, dry mixing and solution mixing, were employed to mix pyrolytic carbon with the activation agent KOH, and their effects were compared. The optimal porous carbon, CPET6-K8-DM, obtained through autogenic pressure carbonization at 600 °C, KOH activation at 800 °C, and dry mixing showed a relatively large specific surface area of 1931 m2/g and decent CO 2 adsorption performance (CO 2 adsorption uptake of 4.44 mol/kg at 101.3 kPa and 25 °C and CO 2 /N 2 selectivity of 7.99). In addition, standard life cycle assessments were used to evaluate the environmental impact of the prepared porous carbon. A comparative analysis revealed that autogenic pressure carbonization has more environmentally friendly characteristics than conventional carbonization conducted under atmospheric pressure conditions for PET waste upcycling. [ABSTRACT FROM AUTHOR]

[Display omitted] • An integrated HTC–PY technique was implemented to valorizes CS and YW. • HTC improved carbon content, deoxygenation, and higher heating value. • CSH and YWH hydrochars' co–pyrolysis modeled via hybrid RSM–ANN. • The pyrolysis of blends reduced the average activation energy. • Pyrolysis of hydrochars enriched bio–oil with hydrocarbons and phenols. Hydrothermal carbonization (HTC) presents a promising method for converting carbonaceous waste into renewable fuels, facilitating energy recovery. This study focuses on the HTC pretreatment of microalgae (Chlorella sorokiniana) and yard waste, examining their physicochemical structural changes, component migration, and potential for valorization via integrated HTC and pyrolysis processes. HTC notably enhances the carbon content while reducing oxygen and nitrogen levels in these feedstocks, producing a clean solid fuel with high energy density. The study investigates the pyrolytic behavior of hydrochars and their blends using different analytical techniques, kinetic modeling, and fixed–bed reactor experiments. The blends with 90% and 70% of microalgae hydrochar (CSH) exhibited the most significant synergistic effects during co–pyrolysis, evident in its devolatilization behaviors and reduced activation energies. Integrating artificial neural networks and response surface methodology models facilitated optimization of pyrolysis parameters and accurate prediction of bio–oil, biochar, and gas yields. The analytical techniques enabled characterization of pyrolysis products, revealing notable changes in bio–oil and biochar compositions, suggesting potential enhancements. The study comprehensively evaluates the HTC–pyrolysis approach's potential for converting microalgae and lignocellulosic biomass into eco–friendly biofuels for industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • EWS-pyrochars are a ready-to-integrate opportunity for soil amendment. • Novel 3D-images reveal the char's porosity, structure, thickness-mesh, and Feret-diameter. • High aromaticity: overall sp2 C-atoms at 63 % in pyrochar vs. 43 % in hydrochars. • High P-retention: 92 % in EWS-pyrochars, near-total in hydrochars. • Hydrochars from a 10-hectare willow may sequester 80-tons of carbon and recover 334 kg of P annually. Willows from engineered wetland systems (EWS) offer a sustainable approach to wastewater treatment and biomass production. Our study assesses their potential for nutrient recovery and carbon sequestration using slow pyrolysis (600 °C) and hydrothermal carbonization (250 °C). Here, we propose EWS-pyrochars as a ready-to integrate opportunity for soil amendment, as they exhibit a predominant CO 2 release and the absence of harmful compounds in pyrolysis-chromatograms, indicating higher stability than hydrochars. Using sequential P-extractions, we observed a high bioavailability in the willow-woodchips and a significant P-retention in EWS-chars—up to 92 % in pyrochars and near-complete retention in hydrochars, along with a higher labile-P fraction of 21 % in hydrochars than 5 % in pyrochars. Utilizing X-ray-based techniques, Raman spectroscopy, scanning electron microscopy, and gas physisorption, we characterized the EWS-chars' structures. We revealed innovative 3D-visualizations, which transcend previous literature by providing insights into the chars' internal porosity and quantifying, for the first time, their carbonaceous structural thickness via a meshing algorithm and the mean Feret diameter. EWS-pyrochars exhibit remarkable aromaticity with a higher concentration of overall sp2 C-atoms at 63 % vs. 43 % in hydrochars. Moreover, unlike hydrochars, which depict occluded porosity, EWS-pyrochars exhibited 92 % water storage-like pores. Although hydrochars indicated lower carbonization and thermal stability than pyrochars, their higher carbon retention (55 vs. 41 % in pyrochar) suggest superior annual benefits—on a 10 ha EWS scale—of 80-tons of carbon sequestration and 334 kg of phosphorus recovery versus 60-tons of carbon and 298 kg of phosphorus with pyrochars. Our findings suggest innovative materials for resource recovery, advancing the engineered wetland systems field, shifting their traditional use, and opening the opportunity for future integration into biorefineries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe2+ substitution generates a P-type doping effect and induces new redox couple of V4+/V5+. • Reaction mechanism of reversible V4+/V5+ has been deeply explored by ex-situ XPS. • Cl− in CHACC infiltrates into the NVP to replace (PO 4)3−. • N element in CHACC results in vast of active sites and defects in the carbon substrate. • Temperature monitoring system analyzes the temperature change and safety of NVP/C-CHACC-Fe0.07 cell. Na 3 V 2 (PO 4) 3 (NVP) has been limited by the poor ionic and electronic conductivity. Besides, the sole redox pair of V3+/V4+ releases a relatively low capacity. Currently, a simultaneous modification strategy of Fe2+ substitution and chitosan quaternary ammonium (CHACC) in-situ carbonization is proposed to optimize NVP for the first time. Fe2+ substitution can generate a classic P-type doping effect to supply abundant hole carries, effectively enhancing the electronic conductivity. Noteworthily, a new redox reaction of V4+/V5+ is activated after Fe-doping, which releases extra reversible capacities at a high voltage platform of 3.9 V, obviously increasing the active capacity and energy density. Moreover, the reaction mechanism of reversible V4+/V5+ has been deeply explored by ex-situ XPS. Furthermore, Cl− in the CHACC infiltrates into the NVP phase to replace part of (PO 4)3−, which can provide a wider migration path and more dedicated space for Na(2) type Na+, improving the ionic conductivity. Moreover, the N element in the CHACC results in vast of active sites and defects in the carbon substrate, which induces the graphitization of hydrogel carbon materials due to the distortion of lattice caused by defects. Comprehensively, the modified NVP/C-CHACC-Fe0.07 shows superior electrochemical and kinetic properties. It reveals a capacity of 121.1 mAh g−1 at 0.1 C. At 30 C and 120 C, it shows capacities of 81.2 mAh g−1 and 70.5 mAh g−1 with retention rates of 72.4 % and 71.2 % after 4000 and 7000 cycles, respectively. Innovatively, temperature monitoring system analyzes the temperature change and safety of the NVP/C-CHACC-Fe0.07 cell, demonstrating that the variate is only 0.8 °C during each cycle. And the temperature remains stable in the long-term operation, suggesting its excellent stability and safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • Species distribution of Na & Cl in kitchen waste and hydrothermal products was quantified. • Feedstocks and cooking method had little effect on Na & Cl migration. • All Na and inorganic Cl ionically flow into liquid phase during hydrothermal carbonization. • The content of organic chlorine retained in hydrochar was 0.21–0.32 wt%. • 90% of organic Cl can be removed by adding Na 2 CO 3 solution or pyrolysis treatment. Hydrothermal carbonization (HTC) is a sustainable approach to recover nutrients from kitchen waste (KW) to realize the applications of hydrochar as fuel, soil amendment and so on. However, the salt content of KW can be as high as 5 wt%, which brings potential risks for product utilization. Thus, the migration path of endogenous (from ingredients) and exogenous (from condiments) Na & Cl in KW during HTC process was investigated. Results showed that the endogenous and total Na element in KW was 0.03–2.98 wt% and 2.97–4.82 wt%, respectively. The main form of sodium was water-soluble (48–82%). The KW feedstocks and cooking methods had little effect on the migration of Na & Cl. During HTC treatment, all sodium element was transformed into water-soluble state, subsequently about 97% was dissolved into the liquid phase. The content of Na element in hydrochar was only below 0.05 wt%, so its negative effect can be negligible. As for the fate of chlorine, the endogenous and total Cl element in KW was 0.31–1.62 wt% and 1.82–3.19 wt%, respectively, and the main form was inorganic Cl accounting for 83–91%. During HTC treatment, about 40–75% of endogenous organochlorine was converted into inorganic Cl by breaking C-Cl bonds, and all inorganic Cl was leached into the liquid phase. In this pattern, partial organochlorine remained in hydrochar with a content of 0.21–0.32 wt%, which need to be further reduced. Methods of adding Na 2 CO 3 solution or HTC-pyrolysis were effective, and approximately 90% of the organic Cl can be removed. Based on the above findings, this study can provide theoretical guidance for the value-added conversion of solid waste with high moisture and high salinity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe/CoC catalysts were developed by hydrothermal and carbonization of Co-MIL-101(Fe). • Fe/CoC exhibited an uncommonly high mineralization (93.38%) and low loss efficiency. • The advantages of Co in activating PMS and Fe in magnetic recycling were exploited. • Fe/CoC/PMS system achieved more than 99 % NOR removal efficiency within 30 min. • Catalyst performance attributed to Co-Fe synergism and adaptive reduction potential. The search for immobilization methods is the key to current research on environmentally friendly catalysts. In this study, Fe-Co bimetallic organic framework material was prepared by microwave hydrothermal method. After further carbonization, structural frame self-fixing catalyst Fe/CoC was obtained for the activation of peroxymonosulfate (PMS). Based on a stable three-dimensional structure, high specific surface area, variable polymetallic ion valence and remarkable catalytic performance, Fe/CoC achieved 99.59 % treatment efficiency and 93.38 % mineralization efficiency of norfloxacin (NOR) within 30 min. The universality was evaluated in multiple antibiotics and actual water configuration solutions. The matching redox potentials and synergistic interactions between the bimetals enhanced the activation catalytic efficiency, which was attributed to the generation of radical SO 4 •− and non-radical 1O 2. In addition, the voltammetry characteristic curve proved the existence of direct electron transfer in the system. Finally, a relatively complete NOR degradation pathways were proposed based on the 13 intermediates. This work has enriched the development of stable catalysts for PMS activation and provided a new idea for MOFs to participate in antibiotic removal. [ABSTRACT FROM AUTHOR]

3D hollow cobalt/carbon fiber with recovery and environmental adaptability to activate PMS for highly efficient pollutant degradation. [Display omitted] • 3D hollow cobalt/carbon fiber (Co-CCF-600) is used for efficient activation of PMS. • As-fabricated Co-CCF-600 has excellent recovery and practical applicability. • The catalyst has a good dynamic degradation rate of carbamazepine. • Reaction mechanisms and possible degradation pathways are discussed in details. Finding effective and practical ways to remove contaminants in the water is a challenging problem, therefore, the construction of recyclable materials has been paid attention to in the practical application of advanced oxidation processes. A three-dimensional hollow tubular surface-loaded cobalt/cotton carbon fiber composite (Co-CCF-600) is successfully prepared by carbonization, which can effectively activate PMS to degrade CBZ. The synthetic Co-CCF-600 degrades 93.47% of CBZ within 60 min. It is worth noting that Co-CCF-600 has good stability and high catalytic activity after 5 cycles, which is attributed to the synergy between Co species (Co0 and CoO) and CCF. In addition, both radical and non-radical processes contribute to the degradation of CBZ, and SO 4 •− plays a dominant role. After a 118 h wastewater degradation experiment, the Co-CCF-600/PMS system still maintains high degradation efficiency and stability. Overall, this study provides an environmentally friendly, low-cost cobalt/carbon fiber material for the removal of CBZ in wastewater and provides a practical solution for environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Laser carbonization was used to prepare 3D MXene-based monolithic electrodes. • CNT-PIC@MXene electrode possessed a high deionization capacity of 46.8 mg·g−1. • PIC and CNTs embedded within the MXene layers enhanced ion accessibility. • The encapsulation of synchronously carbonized PIC inhibits MXene oxidation. Two-dimensional inorganic compounds (MXenes) are considered as advanced materials for capacitive deionization (CDI) in water treatment, however, nanosheet MXenes are highly susceptible to self-stacking and their oxidative stability in aqueous environments is low. In this study, the film-forming properties of polyimide (PI) were employed for facile construction of carbon nanotube (CNT)-bridged MXene films (CNT/PI@MXene) on carbon cloth without the use of binders. CNT/PI@MXene was rapidly laser carbonized to form a three-dimensional (3D) monolithic structure (CNT-PIC@MXene), with the carbonized PI (PIC) acting as an intrinsic pillar and protective shell for Ti 3 C 2 -MXene to prevent stacking and oxidation, while CNT formed interconnections of Ti 3 C 2 -MXene layers to enhance electrical conductivity. The as-prepared CNT-PIC@MXene electrodes possessed a capacitance of 222.3 F·g−1 and exhibited good cyclic stability (100 % capacitance stability after 1000 cyclic voltammetry cycles), and had superior salt adsorption capacity (46.8 mg·g−1, 2.8 mg·g−1·min−1) with 89.7 % desalination retention after 30 CDI cycles. The method developed in this work addresses issues of self-stacking and water-assisted oxidation of Ti 3 C 2 -MXenes and demonstrates binder-free preparation of MXene-based electrodes for CDI desalination applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amino-functionalized lanthanum-based organic framework-derived carbon electrodes were successfully prepared. • Potential impact factors on CDI defluorination performances were evaluated. • A high F−/Cl− selectivity of 56.4 were achieved by using LaBDC/C-NH 2 electrode. • The selective defluorination mechanism of LaBDC/C-NH 2 was provided. Fluoride ion (F−), a prevalent contaminant in wastewaters from industries such as semiconductor manufacturing, metal processing, fertilizer production, and glass making, poses a potential risk to both the ecosystem and public health. Capacitive deionization (CDI) emerges as an innovative electrochemical water treatment technology tailored for selective ionic contaminants (i.e., F−) separation from aqueous solution. In this study, we first developed amino-functionalized La-based metal organic framework (LaBDC/–NH 2) electrode through a solvothermal approach, followed by carbonizing process to produce the LaBDC/C-NH 2 electrode for CDI to selectively capture F−. Our results demonstrated that the carbonized LaBDC/C-NH 2 electrode showed larger specific surface area (9.98 m2/g), superior electrical conductivity, and robust chemical stability. Under a constant current of 2 A/m−2(−|-), the F− adsorption capacity of LaBDC/C-NH 2 electrode was 73.8 mg g−1, which was approximately twice that of the LaBDC − NH 2 electrode and 15 times that of the conventional activated carbon (AC) electrode. The CDI incorporated with the LaBDC/C-NH 2 electrode achieved an impressive F− removal performance, from 8 to 0.17 mg L−1, is achievable, with an associated energy consumption of only 8 kWh kg−1F. Furthermore, when exposed to various co-existed competitive anions, the electrode exhibited outstanding preference towards F− ion (i.e., a high selective factor of 56.52 for F−/Cl−) and maintained its removal capacity even after 10 charging-discharging cycles. X-ray photoelectron spectroscopy (XPS) analysis revealed that F− removal was primarily driven by charge attraction, followed by protonation of the amino group and ion exchange with the hydroxyl group. In addition, density functional theory (DFT) calculated the adsorption energies of La sites for F−, Cl−, NO 3 − and SO 4 2− respectively, and revealed the mechanism of selective F− removal. Our finding showed the development of an advanced metal organic frame (MOF) based electrode for selective F− removal from industrial wastewater. [ABSTRACT FROM AUTHOR]

In this work, we report the high-temperature confinement synthesis of N-doped graphitic carbon shells encapsulated PtCo nanoparticles embedded into porous Ketjenblack (KB) carbon architectures (PtCo@NGCS/KB) for fuel cells by a facile ligand carbonization strategy. [Display omitted] • The confinement synthesis of PtCo@NGCS/KB-800 is achieved by ligand carbonization. • Carbon shell reconstruction effectively improves the accessibility of surface sites. • PtCo@NGCS/KB-800 exhibits more outstanding ORR performance than commercial Pt/C. • PtCo and NGCS synergically account for the enhanced ORR performance. High-temperature reduction technology significantly improves the alloying process but inevitably causes the sintering of metal. Herein, we report the high-temperature confinement synthesis of PtCo nanoparticles encapsulated with N-doped graphitic carbon shells (NGCS) in porous Ketjenblack (KB) carbon architectures (PtCo@NGCS/KB) for fuel cells via ligand carbonization strategy. The optimal PtCo@NGCS/KB-800 exhibits outstanding mass and specific activities (840.2 mA/mg Pt and 0.94 mA/cm2, respectively) for oxygen reduction reaction (ORR), and possesses excellent stability with a smaller peak power density loss rate of 7.1 % than commercial benchmark Pt/C (23.7 %) after the accelerated durability test (ADT) in practical H 2 /air fuel cells. Experimental and theoretical investigations reveal that carbon shell reconstruction improves the accessibility of surface sites, and PtCo and NGCS synergically promote the enhancement of ORR performance. The NGCS encapsulation significantly reduces the energy level of the d-band center of Pt, promotes the desorption of intermediates, and lowers the reaction barrier for efficient ORR. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pre-carbonization enhances yields of activated carbon (AC) at expense of bio-oil. • Pre-carbonization removes aliphatics, creating much less pores from biochar. • ZnCl 2 /H 3 PO 4 as activators form AC of developed pore via biomass direct activation. • Activation with ZnCl 2 /H 3 PO 4 forms little light organics in the bio-oil. • Pre-carbonization led to a higher impact to environment than direct activation. Pre-carbonization is one frequently used pre-treatment for production of activated carbon (AC) from activation of biomass, which impacts not only nature of AC but also composition of bio-oil and gases in activation of biomass. In this study, activation of sawdust/cellulose/lignin directly or via pre-carbonization were conducted, with a particular focus on effects of pre-carbonization on evolution of the various products and environment. The results indicated that the pre-carbonization removed significant portion of aliphatic structures, creating difficulty for developing pores from the resulting biochar. This, however, enhanced overall yields of AC and gases at expense of bio-oil with K 2 C 2 O 4 , CO 2 or H 2 O as activators. The high yield and high specific surface area of AC could not be obtained simultaneously and needs to be balanced in application. In converse, ZnCl 2 or H 3 PO 4 as activators generated more AC with developed pore structures via direct activation of biomass, as they catalyzed the dehydration of aliphatic structures in biomass, but not in biochar. The life cycle assessment (LCA) indicated that the pre-carbonization led to a higher impact to environment and energy consumption than the direct activation. ZnCl 2 and CO 2 showed the smallest influence on the fossil fuel depletion and global warming. Direct activation exhibited lower environmental impact in the production of AC with more developed pore structures, rendering it a more desirable route for production of AC. [ABSTRACT FROM AUTHOR]

• A highly integrated problem-solving solution is proposed for wood-based evaporators. • A generalized laser engraving-driven method is well-demonstrated. • This method yields inorganics with broad-spectrum absorption. • This method allows simultaneous design of the evaporator surface channel structure. • Wood-based evaporators with higher efficiency and more stable output are constructed. Solar interfacial evaporation is recognizable as one of the most prospective strategies to overcome the shortage of fresh water. Recently, there has been growing enthusiasm for the development of wood-based evaporators for solar steam generation. Although such technologies as surface coating and carbonization have been developed, it remains a challenge to cost-effectively manufacture high-efficient wood evaporators under open conditions with long-term serviceability. Here, a generalized laser engraving-driven integrated approach is proposed for simultaneously achieving the conversion of the surface of wood with chelation treatment to carbon and metal oxides and the construction of surface architectures in open environments, resulting in unique stabilized efficient wood-based evaporators. Thanks to the exceptional photothermal conversion properties and stability of carbon and metal oxides, as well as the efficient water transport and the inhibition of dense crystallized salts by the patterned surface structure, the fabricated evaporator exhibits a remarkably more efficient and stabilized output, with evaporation and retention rates of ∼1.72 kg m–2 h−1 and ∼93 %, respectively, surpassing the pristine wood with enhancements of ∼100 % and 120 %, respectively. More impressively, the applicability can be extended to other metal chelates. This work presents a new and sustainable strategy for the development of solar interfacial evaporators utilizing biomass materials. [ABSTRACT FROM AUTHOR]

• Functionalized PAN-Co-C membranes were developed via one-step PAN carbonization. • Co works as a dual-functional catalyst in tuning carbon formation and PMS activation. • All functionalized membranes could activate PMS to generate sulfate radicals. • High permeability was attributed to the formation of graphite carbon and cobalt. • The membrane showed excellent antifouling property with high HA removal. A novel polyacrylonitrile (PAN)-induced carbon membrane with in-situ encapsulated cobalt crystal was developed via a one-step carbonization method and applied for peroxymonosulfate (PMS) activation. The dual-function of cobalt in tuning carbon formation and activating PMS was explored. The growth mechanism of the functionalized membrane was investigated via TGA-DSC, FTIR, XRD, Raman and XPS. Results indicated that the addition of cobalt could tune the formation of C and N containing functional groups in the carbon membrane. The membrane morphologies and surface properties were further characterized by FESEM and AFM. Batch studies revealed that more than 90% of sulfamethoxazole (SMX) could be degraded after 60 min of membranes exposure in the presence of PMS. Electron paramagnetic resonance (EPR) results verified the generation of sulfate radical in this process. The removal of humic acid (HA) in a dead-end membrane filtration mode could be maintained at ∼100% with an inconspicuous sacrifice of permeate flux over 450 min. The permeate flux achieved with PMS was higher as compared to the case without PMS addition, which could be ascribed to the catalytic oxidation of organic molecules accumulated on the membrane surface. The catalytic property imports an intrinsic antifouling property of the carbon membrane in the hybrid catalytic membrane filtration process. [ABSTRACT FROM AUTHOR]

• Poly(furfuryl) alcohol-based porous carbon beads synthesized for the first time. • Carbonized and activated materials contain unique internal morphology. • Non-polar surface structure and polarity of adsorbate affect the VOCs adsorption. • PFAB/C/A is a potential material for VOC adsorption application. Furfuryl alcohol (C 5 H 6 O 2) (FA) was used as the precursor for the synthesis of approximately 1.0 mm sized polymeric beads (PFAB) via suspension polymerization. The polymeric beads were carbonized and activated to synthesize porous carbon beads (PFAB/C/A) as an efficient adsorbent for gaseous volatile organic compounds (VOCs). Surface characterization tests revealed the material to be predominantly microporous with the specific surface area measured to be ∼446 m2/g. Raman measurements revealed a graphitic characteristics of PFAB/C/A. Adsorption tests were performed in a fixed tubular packed bed adsorber under different operating conditions: amounts of adsorbents (2–6 g), gas flow rates (0.2–0.4 standard cc per min), adsorption temperatures (40–60 °C), VOC concentrations (2000–53,300 ppm) and types of VOCs (toluene and benzene). The tests revealed high adsorption capacities of the synthesized material i.e., 515 and 350 mg/g for toluene and benzene, respectively at 50 °C. This study has clearly shown that the biomass-based environmentally benign FA can be a potential alternative precursor to the synthetic petro-based polymers presently used for preparing carbon-based adsorbents. [ABSTRACT FROM AUTHOR]

• Stability of biochars produced at low-medium vacuum was investigated. • Both temperature and vacuum were the most influential factors affecting stability. • Low and medium-vacuum pyrolysis had an overriding effect on biochar characteristics. • Biochar produced under low and medium-vacuum pyrolysis were preferable to biochar stability. Vacuum carbonization is considered to be an effective and promising thermochemical-tool for resource and energy recovery by collecting and reusing pyrolysis products and volatiles. In this study, thermochemical conversion of orange peel to biochar under low- and medium-vacuum pyrolysis conditions were investigated for product distribution and stability characteristics of biochar. The pyrolysis experiments were executed under three different conditions i.e., N 2 atmosphere (without vacuum), low-vacuum (1013.2 Pa) and medium-vacuum (101.3 Pa) in the temperature range of 300–700 °C. The derived biochars were characterized for its aromaticity, polarity, elemental composition, pH, electrical conductivity, surface area, thermal decomposition, FTIR spectroscopy and chemical oxidation properties. Results revealed that low and medium-vacuum pyrolysis had an overriding effect on the H/C (aromaticity) and O/C (polarity) ratios, surface functional groups, as well as on the chemical oxidation potential of derived biochars. A significant reduction in biochar yield (1.1–1.9 folds), increased aromaticity with low H/C (1.3–2.0 folds) and O/C (1.95–4.75 folds) values was observed with increased pyrolysis temperature, under low- and medium-vacuum pyrolysis compared to the N 2 atmosphere. It was also found that biochar produced in the temperature range of 300–700 °C, under low and medium-vacuum pyrolysis were comparatively preferable to biochar stability. It is concluded that biochar produced at low-medium vacuum pyrolysis conditions shows higher carbon sequestration potential compared to the N 2 atmosphere. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mesoporous silica-carbon microspheres (MSCMs) are packed by silica nanospheres with inner aromatic carbon layers. • MSC Ms are controllably synthesized through self-assembly and in-situ carbonization process. • MSC Ms have excellent performances of DBP adsorption through π-π stacking and hydrophobic interactions. Abstract Mesoporous materials have been widely utilized as adsorbents of environmental refractory organics. However, it is a great challenge to synthesize mesoporous adsorbents with controllable pore structures and surface chemical properties. In this study, mesoporous silica-carbon microspheres, aggregated by silica nanospheres with inner aromatic carbon layers, are synthesized through self-assembly and in-situ carbonization process with triblock-copolymer Pluronic P123 as the structure directing agent, tetraethylorthosilicate as the silica precursor, 1,3,5-trimethylbenzene as the swelling agent, and potassium chloride as the spherical micelle inducer. The synthesized silica-carbon materials possess microspherical morphology made of closely packed nanospheres, faced centered cubic mesostructure with space group of Fm 3 ¯ m , large opening mesopores (21.3 nm), high surface areas (491 m2/g) and abundant inner aromatic carbon layers. This microspheres present unique amphiphilic surface that hydrophilic silica of outer layer facilitates well-dispersion in water and helps DBP approach to MSCM by hydrogen bonding, and hydrophobic carbon of inner layer enhances adsorption affinity. Results show an effective adsorption performance in the removal of Di- n -butyl phthalate (DBP) through π-π stacking and hydrophobic interactions. The adsorption of DBP on this adsorbent is an exothermic mono-layer process, fitting to the pseudo-second-order kinetic model, with the maximum adsorption capacity of 57.14 mg/g at 25 °C, the adsorption equilibrium time within 5 min, and DBP removal percentage up to 95% in five cycles. The materials are promising adsorbents of phthalate-like pollutants in water treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new hollow MnFe 2 O 4 -carbon nanospheres (H-MnFe 2 O 4 -C) were synthesized via an in-situ self-etching process. • The mechanism of modification and etching was discussed in detail. • The mesopores H-MnFe 2 O 4 -C shows excellent reversible capacity and cycling stability performance. Abstract The performance of anode materials is critical in further development of Li-ion batteries. However, the reversible capacity and cycling stability of anode materials are still far from satisfying. In this study, a new hollow MnFe 2 O 4 -carbon nanospheres (H-MnFe 2 O 4 -C) synthesized via an in-situ self-etching method was proposed. The MnFe 2 O 4 served as the structural platform to embed the D-galactose coating layer followed by the in situ carbonization, the composite was then etched to form functional mesoporous H-MnFe 2 O 4 -C. The possible formation mechanism were discussed in detail. Based on the advantages of the hollow superstructure, close-packed configuration and uniform carbon coatings, which facilitate lithium-ion and electron transport while simultaneously alleviating the drastic volumetric change during cycling, the H-MnFe 2 O 4 -C exhibit high reversible capacity and outstanding cycling stability (with 973 mAh·g−1 after 500 cycles at the current density of 0.2 A·g−1, and 603 mAh·g−1 at a high current density of 1 A·g−1), as well as high coulombic efficiency (>98%). The findings in this study are useful for the engineering design of porous carbon-coated composite, which can be used for Li-ion batteries applications and other fields. [ABSTRACT FROM AUTHOR]

Highlights • The carbons with different morphologies from biomass sources are reviewed. • Control methods were explored to prepare carbon materials with ordered structures. • The liquefaction path for the degradation and transformation of wood is summarized. • The applications of carbon materials with ordered structures are focused. Abstract Wood has emerged as a sustainable and promising precursor for carbon materials owing to its natural abundance and superb properties. It is of significant importance to prepare carbon materials with different morphologies (carbon spheres, carbon nanowires, carbon membranes, and three-dimensional carbon nanomaterials) and porous structures (disordered and ordered structure) for various fields (adsorption, capacitor, catalyst, solar cells, and sensors). Here, we introduce the characteristics of carbon materials with different morphologies from various biomass sources (Cedar, Starch, Chitin, Straw, Bamboo, and Larch sawdust) and present a comprehensive review of the current research on the development of carbon materials with different morphologies (carbon spheres, carbon membrane, and carbon foams) from liquefied wood. We then introduce control methods (direct carbonization, hydrothermal carbonization, and liquefaction-carbonization) that have been explored to prepare carbon materials with ordered porous structures. Next, we highlight the liquefaction method for the degradation and activity transformation of wood. In particular, we focus on the fabrication, characteristics and applications of carbon materials with different morphologies and porous structures produced from liquefied wood by different control methods (ultrasonic spray pyrolysis, soft template, doping, foaming, and nano-ething). Finally, we present our perspectives on supercapacitors, which need further exploration in the future for urban traffic systems, military equipment, intelligent distributed grid systems, new energy vehicles, solar energy systems, and wind turbine systems. [ABSTRACT FROM AUTHOR]

Graphical abstract Adsorptive desulfurization of DBT on bimetallic porous carbon Zn/Co-MOF. Highlights • Zn/Co bimetallic porous carbon was constructed from a Zn/Co-MOF. • The porous carbon was provided with a high DBT adsorption capacity. • The material had good pore structures, high surface area and large pore volume. • The material also possessed uniformly distributed metal active sites. • Synergistic effects of acid-base and π-π interactions improved ADS performances. Abstract Bimetal porous carbon Zn/Co@C materials derived from bimetal (Zn, Co)-organic frameworks (bi-MOFs) were prepared by a carbonization method in this work. These carbon materials were analyzed by some characterization technologies including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), N 2 adsorption–desorption, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), Raman spectra, Zeta potential and Boehm titration. The results demonstrated that an optimal carbonization temperature was 800 °C. The material prepared under such condition (denoted as Zn/Co@C-800) had good porous structures, uniformly distributed metal active sites, high surface area (531.1 m2 g−1) and large pore volume (0.449 cm3 g−1). In addition, adsorption desulfurization performances of samples for dibenzothiophene (DBT) were systematically investigated and followed an order: Zn/Co@C-800 > Zn@C-800 > Zn/Co@C-600 > Zn/Co@C-700 > Zn/Co@C-900 > Co@C-800. Pseudo second-order kinetic and Langmuir models presented best fitting results of DBT adsorbing on Zn/Co@C-800. The Zn/Co@C-800 exhibited the remarkable adsorption capacity of DBT (40.6 mg g−1) due to positive bimetallic synergistic effects. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Fe-crosslinked sodium alginate was carbonized to synthesize Fe/C composite. • Fe/C composite with high content of reductive Fe was successfully prepared. • Fe/C composite had a high Cr(VI) removal capacity due to reduction and adsorption. Abstract It is vital to prepare iron (Fe)-containing porous carbonaceous materials (Fe/C) with high reductive Fe content, large specific surface area, and abundant oxygen-containing functional groups to alleviate the toxicity and mobility of Cr(VI) from both reduction and adsorption. In this study, Fe-crosslinked sodium alginate (SA-Fe) was carbonized to prepare an Fe/C composite (SA-Fe-C) with high content of reductive Fe content for Cr(VI) removal via regulating the amount of crosslinked FeSO 4. With increasing FeSO 4 from 1 mmol to 10 mmol, the main Fe components in the Fe/C composite transformed from FeS and Fe 3 O 4 to Fe(0), and the content of reductive Fe increased from 81.2 mg to 120 mg. The optimal dosage of FeSO 4 was 10 mmol, at which obtained SA-Fe-C with higher content of reductive Fe (i.e., Fe(0) FeO, and FeS), specific surface area, and rich oxygen-containing functional groups. The prepared SA-Fe-C exhibited a high removal capacity for Cr(VI) (100 mg/g) due to the high content of reductive Fe, which accounted for 84.0% of Cr(VI) (20 mg/L) reduction. The adsorption resulted from pore-filling and cation bridging and/or strong charge-assisted H-bonding contributed to 16.0% of the total removal of Cr(VI). Our findings showed that Fe/C composite with high content of reductive Fe and large specific surface area can be regulated and has a promising application potential in remediating heavy metals contaminated water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A series of CoO x @PC-T derived from ZIF-67are successfully prepared. • The carbonization of ZIF-67 is related to the pyrolysis temperature. • The carbonization degree affects the exposure and oxidization of cobalt particles. • CoO x @PC-800 shows the highest de-NO x performance. Abstract Herein, a series of Co 3 O 4 nanoparticles inlaid in porous carbon (CoO x @PC-T) were successfully prepared via first pyrolysis of ZIF-67 in argon atmosphere at different temperature and then oxidized in 5% O 2 /Ar mixed gas. The as-made samples were employed as catalysts for selective catalytic reduction of NO x with NH 3 at low temperature (100 °C–200 °C). The effect of pyrolysis temperature on the microstructure, textural properties, and chemical properties of CoO x @PC-T were characterized by TG-MS, BET, XRD, SEM, TEM, H 2 -TPR and XPS in detail. Results show that the pyrolysis temperature has a significant effect on the carbonization degree of carbon in ZIF-67, and which in turn affects the exposure and oxidization of cobalt nanoparticles on the catalyst surface. Experiments results show that CoO x @PC-800 display the highest NO x conversion ratio, which is attributed to its higher ratio of Co3+/Co2+ and large specific surface area. Moreover, the stability, H 2 O and SO 2 resistance of CoO x @PC-800 were also studied. [ABSTRACT FROM AUTHOR]

Highlights • Coral-like NiCoP@C@Ni(OH) 2 nanoarrays are vertically grown on nickel foams. • The cycling performance of NiCoP@C@Ni(OH) 2 has been increased from 53.5% to 81.2%. • Hybrid supercapacitor delivers a high energy density of 49.5 Wh kg−1 at 399.8 W kg−1. Abstract Transitional metal phosphides (TMPs) are regarded as comparatively promising electrode materials for energy storage and conversion. However, the poor cycling performance of TMPs remains to be a major challenge of their practical application for supercapacitor. In this work, coral-like NiCoP@C@Ni(OH) 2 core-shell nanoarrays are vertically grown on nickel foams using two-step hydrothermal reaction, followed by carbonization and phosphorization treatment. The participation of amorphous carbon layer and ultrathin Ni(OH) 2 nanosheets is expected to improve the performance of cycling stability and energy density. This NiCoP@C@Ni(OH) 2 NAs exhibit high specific capacitance of 2300.8 F g−1 at a density of 1 A g−1, good rate capability (72.1% of capacitance at 20 A g−1) and long-term cycling stability (81.2% retention after 3000 cycles at 10 A g−1). Moreover, with the help of ultrathin Ni(OH) 2 nanosheets, a hybrid supercapacitor assembled by the NiCoP@C@Ni(OH) 2 NAs electrode against activated carbon achieves a high energy density (49.5 Wh kg−1 at a power density of 399.8 W kg−1). These results demonstrate that such NiCoP@C@Ni(OH) 2 NAs hold great promise as novel battery-like electrode for hybrid supercapacitors in energy conversion. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The novel flexible Mn-based CNFs were successfully prepared by electro-blow spinning method and carbonization process. • The modified Li metal battery exhibits the stable Li deposition–stripping behavior. • The battery with the prepared interlayer presented better rate capacity, high cycling stability and low impedance. Abstract In this work, the novel flexible Mn-based carbon nanofiber interlayers were rationally designed and prepared by electro-blow spinning and carbonization method. Especially, the representative MnS carbon nanofiber (MnS-CNFs) films and MnF 2 porous carbon nanofiber (MnF 2 -PCNFs) film were respectively applied as interlayer to hybridize with Li as composite anode to investigate their application performance. After systematic research, the cyclic stability of interlayer modified LCO-Li batteries (MnS-CNFs: initial capacity of 143 mAh g−1 and retention rate of 70% after 100 cycles, MnF 2 -PCNFs: initial capacity of 137 mAh g−1 and retention rate of 90% after 100 cycles) were obviously improved when compared with pristine LCO-Li battery (initial capacity of 133 mAh g−1 and retention rate of 45% after 100 cycles) at the current density of 3 mA cm−2. The modified symmetric Li battery exhibits stable Li deposition-stripping behavior without cell short-circuit during 150 cycles. The higher performance of modified battery compared with pure Li metal battery might be attributed to the introduction of flexible Mn-based carbon nanofiber interlayers. On the one hand, the flexible films with self-support and porous structure could act as transitional layer to accommodate the volume expansion of Li metal and facilitate more Li insert into the interior/surface of carbon nanofibers. On the other hand, the 3D interconnected carbon nanofiber skeletons doped MnS and MnF 2 could provide more active sites to guide the Li deposition and stripping more sufficient and homogeneous. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlight • A novel GPCA aerogel was fabricated to enhance SMX degradation in neutral E-Fenton. • γ-FeOOH was synthesized in situ into the carbonized aerogel framework. • Catalytic stability of GPCA-EF was greatly enhanced compared with traditional CF-EF. • Three possible pathways of SMX in GPCA-EF system was given. Abstract Novel γ-FeOOH graphene polyacrylamide carbonized aerogel (γ-FeOOH GPCA) was used as the cathode in neutral electro-Fenton (EF) process to achieve degradation and mineralization of sulfamethoxazole (SMX). γ-FeOOH GPCA cathode was fabricated by a multiple-phase carbonization method, leading to a good conductivity (26.37 Sm−1 with 7.5 mg mL−1 GO) and high electrochemically active surface area (EASA). An in situ synthesis method of γ-FeOOH was accomplished to distribute the catalyst uniformly and firmly into the carbonized aerogel framework. Two electron reduction could take place at the cathode, H 2 O 2 and Fe2+ can be generated at GPCA cathode efficiently. A 5-batch comparative assessment between GPCA-EF and CF-EF process exhibited the distinguished catalytic stability of GPCA cathode with a total organic carbon (TOC) removal efficiency of 89.8 ± 0.8%, 89.1 ± 0.9% and 84.7 ± 1.1% at the last 3 batches, respectively, versus 61.2 ± 1.2, 60.9 ± 1.1 and 59.4 ± 0.9% by CF cathode. This carbonized aerogel cathode demonstrated a great potential for the EF process to remove organic pollutants in water at neutral pH. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • N-doped porous carbons were synthesized by one-step NaNH 2 activation of carbonized water chestnut shell. • The activation temperature ranges from 400 to 500 °C. • Water chestnut shell derived carbon exhibits high CO 2 uptake, 4.5 mmol/g at 25 °C and 1 bar. • N-doped porous carbons adsorbed CO 2 rapidly and had excellent cyclability. • Nitrogen content, pore size and volume of narrow micropore are key factors in determining CO 2 uptake. Abstract The aim of this study is to exploit low-cost N-doped porous carbonaceous adsorbents with excellent CO 2 adsorption properties. Herein, the N-enriched porous carbons were obtained through a single-step sodium amide activation of carbonized water chestnut shell at 400–500 °C. The optimal sample possesses high CO 2 uptake of 4.50 mmol/g (25 °C) and 6.04 mmol/g (0 °C) at atmospheric pressure. Additionally, this sample displays high CO 2 /N 2 selectivity, stable cyclic ability, moderate CO 2 isosteric heat of adsorption, fast CO 2 adsorption rate, and high dynamic CO 2 uptake. In addition to the two well-known factors i.e. volume of narrow micropore and N content, the pore size distribution is also found to play major role in deciding CO 2 adsorption performance for these adsorbents. The features of excellent CO 2 adsorption properties, low-cost raw materials, low reaction temperature and facile preparation demonstrate that these adsorbents are prospective in the application of CO 2 capture. [ABSTRACT FROM AUTHOR]

Highlights • N/S codoped carbon microboxes is prepared via a carbonization-etching process. • The NSC delivers super-long cycle life and extraordinary rate ability. • The excellent performance is attributed to the large interlayer spacing of NSC. Abstract Carbonaceous materials for potassium-ion batteries (PIBs) are quite attractive for the cost-effective feature. However, the cycle stability and rate performance of carbonaceous anode materials based on PIBs are limited, for the difficulty of accommodating large K ions (1.38 Å). Thus, the nitrogen (N) and sulfur (S) codoped carbon microboxes (NSC) with increased interlayer spacing is prepared via a carbonization-etching process. Unlike the traditional graphite, in which the K ions are difficult to insert into the restricted interlayer spacing, the NSC displays extremely large interlayer spacing of 0.412 nm, making the K ions more flexible during the insertion/extraction process in NSC. Moreover, ex-situ TEM study reveals that the layer structure of NSC is well-remained during the potassiation/depotassiation process. As a result, the NSC delivers super-long cycle life (180.5 mAh g−1 at 500 mA g−1 after 1000 cycles) and extraordinary rate ability (155.6 mAh g−1 at 2 A g−1), which makes the NSC a promising anode material for PIBs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A asphaltene-based nanoporous carbon (IANC) was successfully synthesized. • The IANCs showed high S BET (up to 2186 m2/g) and V total (up to 1.3 cm3/g). • The IANCs inherently possessed N (up to 2.69 wt%) and S (up to 0.96 wt%). • CO 2 and H 2 S uptake of IANCs reached 7.15 and 12.86 mmol/g at ambient conditions. • The synthesized IANCs also showed efficient performance in cyclic regenerations. Abstract The development of waste-derived nanoporous carbon, especially from petroleum wastes, as a challenging type of contaminants, has drawn tremendous attention during the past decade. In this work, for the first time, a novel N-S-rich nanoporous carbon possessing high value-added and porosity, was prepared from asphaltene residue through a simple chemical activation. After carbonization of the precursor at 450 °C, chemical activation by different KOH/C ratios (2:1 to 5:1 g/g) was followed which resulted in the formation of unique micro-mesoporous structures (named as IANC samples). The results displayed that large surface area (up to 2186 m2/g) and pore volume (up to 1.3 cm3/g) were obtained. The IANC samples showed outstanding CO 2 and H 2 S uptake at both atmospheric (7.15 mmol/g for CO 2 and 12.86 mmol/g for H 2 S at 1 bar and 25 °C) and high pressures (29.29 mmol/g for CO 2 and 38.61 mmol/g for H 2 S at 35 bar and 25 °C). Furthermore, the IANCs exhibited excellent selectivity for CO 2 /CH 4 , H 2 S/CH 4 and CO 2 /N 2 samples. To better understand the interactions mechanism between adsorbent and each adsorbed molecule and also to determine the active sites in the adsorption process, the density functional theory (DFT) method was employed. The quantum chemistry calculations elucidated the exciting impact of defected nitrogen and sulfur sites in enhancing adsorption interaction of H 2 S and CO 2. Besides the fascinating gas uptake and the preferential gas adsorption, the synthesized IANCs possessed high heat of adsorption and stable cyclic adsorption-desorption ability. Considering the inexpensive cost of asphaltene along with the desired adsorption properties, the asphaltene-derived activated nanoporous carbon (i.e., IANC) can be a promising candidate for superior gas adsorption. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The nanostructured octahedral C-Pd/Cu catalyst was synthesized via directly carbonization of pristine Pd@Cu(BTC). • The selectivity of C-Pd/Cu catalyst was predicted by DFT calculations before experiments were conducted. • The selectivity towards alcohol products was improved to 93.2% when C-8 wt% Pd/Cu was used as catalyst. Abstract In order to directionally convert CO 2 into liquid fuels, Cu(BTC) doped with Pd nanoparticles was carbonized to obtain a novel octahedral catalyst C-Pd/Cu for selective reduction of CO 2 to alcohol products. XRD patterns showed that Cu characteristic peak in C-8 wt% Pd/Cu catalyst shifted to the lowest angle at 2θ=43.22°among all the prepared catalysts (2θ C-1.6 wt% Pd/Cu = 43.3°, 2θ C-4.8 wt% Pd/Cu = 43.29°, 2θ C-11.2 wt% Pd/Cu = 43.26°, 2θ C-14.4 wt% Pd/Cu = 43.28°). The inter planar distance of Cu nanoparticles in C-8 wt% Pd/Cu catalyst was 2.0915 nm, which was larger than those in other catalysts. XPS spectra showed main peak shift to lower binding energy, representing the influence of Pd doping to Cu. SEM and TEM indicated that many ∼70 nm Cu particles and ∼10 nm Pd nanoparticles uniformly distributed in ∼250 nm porous carbon-based octahedral particles. Raman spectrum implied that C-Pd/Cu catalyst with many defects (band ratio I D /I G = 0.84) provided more active sites for intermediates adsorption and facilitated electron transfer. BET result showed C-Pd/Cu catalyst had many mesporous. It was found by density functional theory (DFT) calculations that C-Pd/Cu catalyst had good selectivity towards alcohol products such as methanol, the reaction energy towards producing CH 3 OH was 19.5 eV lower than that of producing HCOOH. The pathway CO 2 → COOH∗ → CO∗ + H 2 O → COH∗ → HCOH∗ → CH 2 OH∗ → CH 3 OH was the most favored to produce CH 3 OH. CO 2 photoelectrochemical reduction reaction was then conducted in a photoelectrochemical reduction cell (PEC) to verify the calculation result. The total carbon atom conversion rate over C-8 wt% Pd/Cu catalyst reached 2380 nmol·h−1 cm−2 with a high liquid products selectivity towards alcohol products, which was in good agreement with DFT calculation results. And the PEC system was proved to have more energy input under the same applied voltage compared with the electrochemical system. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Large scale synthesis of ZnO tetrapods by flame transport synthesis. • Eco-friendly extraction of activated carbon from sugarcane. • ZnO tetrapods-activated carbon based advance composite fabrication. • ZnO tetrapods-activated carbon composites as efficient Cr(VI) adsorbents. Abstract Owing to its acute toxicity and mobility, the hexavalent chromium [Cr(VI)] in water and wastewater is an immense risk to the environment. Herein, ZnO-tetrapods/activated carbon (ZnO-T/AC) nanocomposite was synthesized as an adsorbent for an efficient decontamination of Cr(VI) from an aqueous medium. The tetrapodal ZnO was synthesized by flame transport synthesis (FTS) approach. The utilized activated carbon (AC) was successfully prepared from sugarcane bagasse with sodium hydroxide (NaOH) impregnation, followed by carbonization. Finally the ZnO-T/AC nanocomposite was synthesized by the hydrothermal method. The structural and chemical properties of the obtained nanocomposite (NC) were systematically characterized using X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and Brunauer–Emmett–Teller (BET) analysis. Batch experiments were performed with the AC, ZnO-T and ZnO-T/AC to study their maximum adsorption efficiency for the Cr(VI). The effect of operational parameters such as contact time, pH and adsorbent dosage on the removal of Cr(VI) were also investigated. Different kinetic models were employed to comprehend the adsorption mechanism. The removal efficiency (97%) of Cr(VI) using ZnO-T/AC adsorbent was achieved at pH 2. The synthesized nanocomposite showed significant potential for the decontamination of Cr(VI) and can be further explored at a large scale for the efficient removal of hazardous heavy metal ions from the industrial contaminates. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A N and P dual-doped carbon derived from chitosan used as cathode catalyst. • The MPD was 1603.6 ± 80 mW m−2, 5 times as high as the control. • The phosphating increased the OCP, surface area, and transformation of graphitic-N. • Co-doped carbon increased the content of C O and the active sites caused by defects. Abstract Carbon derived from chitosan, followed by phosphoric acid activation during thermal treatment to obtain N and P dual-doped catalyst, is studied as the catalyst for air–cathode in a microbial fuel cell (MFC). The maximum power density (MPD) of 1603.6 ± 80 mW m−2 is achieved, which is 5 times as high as that of the control (322.4 ± 16 mW m−2) when N, P-codoped carbon was calcined at 850 °C. The better performance is due to a higher open circuit potential, lower total resistance and higher exchange current density. In addition, the optimized catalyst possessed the largest specific surface area of 982.18 m2 g−1, so it could transfer more oxygen and supplied added active sites. And the existence of graphitic nitrogen, phosphorus and high content of carbon oxygen bonds promoted the cathode performance in MFC. In brief, the N and P dual-doped carbon from chitosan was potentially low-cost catalyst for the high performance of MFC. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Novel carbon-supported Co (CS-Co) composites were synthesized by carbonization process from a saturated cationic resin. • The composites exhibit excellent PMS activation for TMP degradation. • Scavenging tests confirmed SO− 4 and OH were the dominant reactive radicals. • Normalized steady-state concentrations of SO− 4 and OH were calculated. • TMP degradation pathways were proposed based on the identified intermediates. Abstract We first report the syntheses of carbon-supported Co (CS-Co) composite via a carbonization process from a saturated resin. CS-Co exhibited favorable catalysis activities in activation of peroxymonosulfate (PMS) to generate SO− 4 and OH for trimethoprim (TMP) degradation. The performance of composites were studied with respect to diverse pHs (3.0–9.0), catalyst dosages (0.05–0.5 g/L), PMS dosages (0.05–1.0 mM), TMP concentration (5–20 mg/L) and temperature (15–30 °C). Water matrix concerning various levels of humic acid (HA) showed negative effect for TMP removal due to the intrinsic competition between HA. Scavenging test indicated that SO− 4 and OH were the dominant reactive radicals, and an uncomplicated method to calculate the normalized steady-state concentration of radicals in CS-Co/PMS process was established. The electron transfer concerning PMS, carbon surface and Co2+ was attributed as the main activation mechanism. The main intermediate products of TMP were identified by LC/MS/MS technology with four degradation pathways proposed, including hydroxylation, electron transfer mechanism, demethylation and ring-cleavage. [ABSTRACT FROM AUTHOR]

Persulfate decontamination technologies utilizing transition metals as activators has been widely concerned for the treatment of organic contaminants; however, how to securely anchor active substances to heighten stability and introduce heteroatoms into carbon skeleton to improve catalytic activity are still facing great challenges. Herein, nitrogen/cobalt-codoped multifunctional carbonaceous beads (MCB, SA/N-Co x O y -X) have been successfully prepared by employing renewable sodium alginate and melamine via sol–gel assembly and carbonization methods. Compared to other related works, the acylation of nitrogen and the chelation reaction between carboxyl and cobalt can effectively stabilize nitrogen and cobalt, thus leading to a high dispersion and stabilization of heteroatoms. Characterization and catalysis experimental results identified that nanoparticles were embedded on SA/N network in-situ rather than surface. Different decoloration systems were carefully optimized, which illuminated that the surpassing efficiency was attributed to the synergy of nitrogen, carbon skeleton and cobalt species. More importantly, the broad-spectrum degradation capability of the catalyst was evaluated by efficiently degrading of several typical organic pollutants, such as ponceau, p-nitrophenol and tetracycline. Additionally, even after being used for ten times, catalyst still maintained high activity, which indicated its excellent stability. Besides, the coexisting anions and quenching experiments showed that both SO 4 − and OH were the two main radicals and SO 4 − possessed widely scope application conditions, which was hardly affected by common anions. Finally, by virtue of the developed porous structure, unconventional electrons distribution and expanded texture, this type of semiconductor-like SA/N-Co x O y -X would be promising candidate for PMS activation and would possibly shed light on other fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni@SiC@C double-shell nanoparticles were dispersed into CNFs by electrospinning. • Carbonization temperature is the critical for optimizing impedance matching. • The N-doped defect introduces extensive defects to generate dipole polarization. • The dispersed double-shell nanoparticles can provide abundant interface polarization. Achieving a broad bandwidth and efficient absorption of electromagnetic wave absorption materials remains a significant challenge, especially when considering electromagnetic pollution protection. One-dimensional carbon nanofibers with a three-dimensional network structure have been extensively studied to address this need. However, the high permittivity of carbon nanofibers results in a strong impedance mismatch with free space. In this work, we successfully dispersed double-shell Ni@SiC@C nanoparticles into one-dimensional carbon nanofibers (Ni@SiC@C CNFs) using electrospinning and heat treatment. We extensively explored the effect of carbonization temperature on the impedance matching and magnetic-dielectric loss for electromagnetic wave. The presence of rich interfaces from the double-shell nanoparticles and defects from N-doping optimizes the impedance matching of the composites. The exceptional electromagnetic wave absorption properties of the Ni@SiC@C CNFs are attributed to the synergistic effect between the three-dimensional conductive network, the interface electronic engineering induced by the sensibly loaded double-shell nanoparticles, and the multiple reflections, especially at a carbonization temperature of 600 ℃. The achieved minimum reflection loss value has been measured at an outstanding −53.27 dB, coupled with a remarkable absorption bandwidth that spans from 2.53 GHz to 18.00 GHz (15.47 GHz) across various thicknesses. These findings underscore the potential of the meticulously engineered Ni@SiC@C CNFs as highly promising candidates for efficient and broadband electromagnetic wave absorption applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • ANF-carbonized welding is used to reduce the ITR of 3D graphene architecture. • PCM containing graphene architecture shows a TC of 4.85 W/mK at 4.26 vol% content. • Thermal conductive architecture achieves the rapid heat transfer/storage in PCM. • Graphene architecture enables PCM solar/electric-to-thermal conversion capacity. Graphene-based porous architectures are promising in addressing the poor thermal conductivity, leakage, shape stability problems of organic phase change materials (PCMs), meanwhile endowing them with excellent solar/electric-to-heat conversion ability, but they are still limited by the high interfacial thermal/electrical resistance in architectures caused by organic "binders". In this work, in view of the excellent gel ability of aramid nanofibers (ANF) and its highly ordered conjugate molecular structure, a promising graphene porous architecture assisted by ANF was constructed by unidirectional freeze casting coupled with carbonization welding technique. Due to the similar graphite lattice structure of ANF-derived carbonization and graphene, the interfacial thermal/electrical resistance in highly vertically oriented graphene architecture was greatly reduced. As a result, the PCMs composite encapsulated by the graphene architecture carbonizing at 1500 °C exhibited an outstanding thermal conductivity of as high as 4.85 W/mK at only 4.26 vol%, which enables a rapid heat transfer and storage in PCM composite. The honeycomb porous graphene architecture with high porosity can accommodate sufficient PCMs for energy storage, showing a high latent heat enthalpy of 149.7 J/g with excellent shape stability during phase change process. More importantly, the graphene architecture endows PCM composites with excellent solar/electric-to-thermal conversion capacities, which not only expands the types of energy stored by PCMs, but is also promising in the thermal management application requiring a continuous and stable temperature environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn 3 O 4 /AC nanocomposites were prepared from the spent coffee grounds. • The formation mechanism of Mn 3 O 4 /AC was explained. • Mn 3 O 4 /AC exhibited high adsorption ability for MB (q max = 77.02 mg/g). • The composite exhibited excellent reusability and stability. Recently, the recycling and reuse of biomass wastes to produce valuable materials have garnered significant attention due to their substantial economic and environmental benefits. In this study, spent coffee grounds (SCGs) were utilized to prepare nanocomposites through a one-pot carbonization approach under optimal conditions of 550 °C, 2 h, and 1:0.5 mass ratio of SCGs to MnSO 4 ·H 2 O. The produced Mn 3 O 4 /activated carbon nanocomposites (Mn 3 O 4 /AC) were employed for adsorption studies of methylene blue (MB). The mechanism of Mn 3 O 4 /AC formation was comprehensively elucidated, and its morphological and structural features were determined by XRD, SEM, FTIR, TEM, and BET methods. Batch experiments were performed to examine the effect of different parameters on the adsorptive removal of MB. The findings have demonstrated a maximum uptake of Mn 3 O 4 /AC for MB at 77.02 mg g−1. The most appropriate models for predicting the adsorption kinetics and equilibrium data were determined to be the pseudo-first-order kinetic model and the Freundlich isotherm, respectively. Furthermore, the composite exhibited remarkable reusability and stability, retaining over 90% of MB removal efficiency even after undergoing five cycles of reuse. The adsorption mechanism of the dye was clarified based on the physical properties of the adsorbent, including stacking interactions, pore-filling, hydrogen bonding, and electrostatic interactions. The Mn 3 O 4 /AC composite holds promise for future investigations concerning wastewater-containing dyes. [ABSTRACT FROM AUTHOR]

• Catalytic co-pyrolysis of CS/HDPE over N-doped activated carbon was studied. • The synergistic activation of urea and KOH enhanced specific surface area and micropore ratio. • N-doped activated carbon significantly promoted the generation of monocyclic aromatics. • The introduced pyridinic-N and pyrrolitic-N showed excellent catalytic activity. • Excessive nitrogen doping resulted in the formation of polycyclic aromatics. Nitrogen-doped activated carbon catalysts (NAC) were prepared via a two-step process involving the co-carbonization of coconut shell and urea, followed by activation with KOH. These NAC were then employed in the catalytic co-pyrolysis of corn stover (CS) and high-density polyethylene (HDPE) using a fixed bed reactor. The characterization results demonstrated that nitrogen doping led to a larger specific surface area, an enhanced microporous structure, and abundant nitrogen-containing functional groups, which facilitated the production of liquid and promoting the selectivity of monocyclic aromatics (MAHs). The introduced pyridinic-N and pyrrolitic-N provided sufficient active sites for deoxygenation, cracking, aromatization, and Diels-Alder reactions of co-pyrolysis vapors that augmented the formation of MAHs, as well as high calorific value syngas including H 2 , CH 4 , and C 2+ hydrocarbons. The highest MAHs yield of 62.41% was achieved at a urea to coconut shell ratio of 0.8, whereas an excessive amount of urea resulted in cyclization and polymerization reactions of MAHs to form polycyclic aromatics (PAHs). Accordingly, controlling temperature and catalyst to raw material ratios enabled further regulation of the production and selectivity of MAHs. NAC with a better pore structure and more active sites exhibited excellent catalytic activity for value-added MAHs production in the co-pyrolysis of CS and HDPE, benefiting the resource utilization of organic solid waste with carbon-based catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pre-oxidation enhances specific surface area by 54.6% in CO 2 activation and 30.0% in H 2 O activation. • O 2 breaks rigid structure of biochar, forming activated carbon of microporous with larger diameters. • O 2 promotes conversion of olefinic C = C to aromatic C = C in activation, accelerating aromatization. • Promoting pores formation of O 2 is confirmed in activation of cellulose, pine needle and spirulina. Carbonization plus activation of resulting biochar is a commonly used method for producing activated carbon (AC) from biomass. Nevertheless, carbonization produces biochar of highly aromatic nature, increasing difficulty for creating pores via activation. Herein, O 2 (7.7%) was introduced to pre-oxidize lotus root and other biomasses-derived biochar before being activated with CO 2 or H 2 O for tackling chemical inertness of biochar at 800 °C. The results indicated that O 2 could enhance mass yield of AC (by 16.5% in CO 2 activation and 50.6% in a H 2 O activation) and bio-oil. Moreover, O 2 oxidized organics on AC, forming oxygen-containing aliphatic structures. Such a transformation enhanced reactivity of biochar with CO 2 or H 2 O, facilitating generation of pores. The AC from activation with O 2 -CO 2 was significantly higher than that from CO 2 alone (533.7 m2 g−1 of AC from O 2 -CO 2 activation versus 345.2 m2 g−1 of AC from CO 2 activation). O 2 also could remarkably increase the specific surface area of AC activated with H 2 O by 30.0%. Such an enhancement in pore structures was confirmed in activation of cellulose, pine needle and spirulina with O 2 presence. The pre-oxidation activated biochar destroyed partially rigid structure, facilitating gasification with CO 2 /H 2 O, forming dominantly micropores with enlarged diameters. The characterization with in-situ IR indicated that O 2 could enhance aromatization via aiding formation of aromatic C = C from olefinic C = C, producing AC of more regular alignments of carbon crystals. [ABSTRACT FROM AUTHOR]

[Display omitted] • First reviewed porous pADC and pPDCs, especially for the applications in adsorption. • The preparations and the surface properties of the pADC or pPDC adsorbents were detailed. • The adsorption results were discussed in preconditions and mechanisms. • Prospects of pADC and pPDCs in adsorptions and the relevant fields were suggested. Nitrogen-doped porous carbons are one of the most fascinating materials with noticeable applications in adsorption/separations, catalysis, supercapacitors, and batteries. Polyaniline (pANI)- or polypyrrole (pPYR)-derived carbons (pADCs or pPDCs, respectively) exhibit very remarkable performances in the liquid- and gas-phase adsorptions because of some unique characteristics including nitrogen- and oxygen-functionalities, very high specific surface area, and tailored porosity. In this report, we reviewed the recent advances in the preparation and characterization of pADC- and pPDC-type materials and their applications in the adsorptive removal/separation of various chemicals from water, liquid fuel, and air. The preparation procedures and the surface properties of the reported pADC or pPDC adsorbents were explained, with adequate tables. The adsorption results were discussed in terms of the following points: (i) maximum adsorption capacities of the pADCs or pPDCs for a specific adsorbate, (ii) possible adsorbate-adsorbent interactions to understand the adsorption mechanisms, (iii) regeneration of pADC or pPDC adsorbents for recyclability. We believe that this review will provide new scientific perceptions to design/optimize highly porous carbons, especially pADCs or pPDCs, for various applications including adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nanoring-like N, P co-doped carbons were constructed by the carbonization and phosphidation of MOF@MOF. • NPC-Rings-based CDI cell obtained a large salt adsorption capacity of 43.0 mg g−1. • NPC-Rings achieved superior cycling performance over 100 cycling cycles. The developments of efficient carbonaceous materials are of significant importance to break through the bottlenecks of the traditional electrodes for capacitive deionization (CDI). Herein, we reported a simultaneous MOF-on-MOF growth combined with the MOF-etching strategy for the tailoring of MOF/MOF nanorings. Afterwards, N, P co-doped carbon rings (NPC-Rings) was synthesized through the thermal transformation of MOF/MOF nanorings and followed by the phosphidation activation. Taking advantage of such hierarchically porous structures, the NPC-Rings exhibited a high adsorption capacity of 43.0 mg g−1 in a 500 mg L−1 NaCl solution, fast salt adsorption rate, and superior capacity retention stability of 90.4% after 100 cycles. Finite element simulations further revealed that the unique structure of the NPC-Rings considerably promoted the current density and generates charge migration, thereby providing stronger salt adsorption capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal carbonization (HTC) enhances fuel ratio and calorific value in hydrochar. • Hydrolysis reactions during HTC differentiate it from other thermochemical processes. • Microalgal hydrochar has applications in energy, environment and agricultural fields. • CEC and oxygenated functional groups promote adsorption capacity of algal hydrochar. • Integrating HTC with AD can lead to self-sustaining energy generation strategy. Exploitation of microalgal biomass as a valuable resource is hindered by the challenges associated with high downstream processing costs, including biomass harvesting, drying, and product extraction. Direct utilization of microalgae as a solid fuel source, soil conditioner, capacitor or adsorbent material raises environmental concerns. Hydrothermal carbonization (HTC) is a highly efficient and promising technology for microalgal biomass conversion. This comprehensive review provides an in-depth understanding of the HTC reaction mechanisms involved in microalgal hydrochar production, shedding light on the underlying processes and factors affecting the quality of hydrochar. HTC has the potential to improve fixed carbon content, thermal stability and nutrient availability in the resulting hydrochar. Furthermore, this review explores the integration of HTC with anaerobic digestion (AD) to establish a circular bioeconomy, thereby promoting sustainability in energy generation. The synergistic combination offers a promising approach for the efficient utilization of microalgal biomass, where hydrochar can serve as a renewable energy source while the aqueous fraction can be utilized as a nutrient-rich feedstock for biogas production. By highlighting the potential benefits and futuristic directives associated with microalgal biomass valorisation through HTC, this review aims to contribute to the development of sustainable waste management strategies for recovery of value-added compounds from microalgae. Ultimately, this review strives to foster the transition towards a more environmentally friendly and resource-efficient bioeconomy. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work provides insights of the HTC-AP valorization pathways. • The properties of the AP from HTC of different feedstock types were compared. • Effects of feedstocks and HTC conditions on the AP composition were elucidated. • Applications of HTC-AP were evaluated, obstacles and solutions were proposed. • Merits and demerits of technologies for HTC-AP purification were highlighted. Hydrothermal carbonization (HTC) is a promising method for converting wet solid waste into value-added products. Despite the extensive research on the HTC solid fraction, the HTC aqueous phase (AP) has received limited attention. Due to the complex composition of HTC-AP, conventional decontamination technologies are often expensive and inefficient, while causing a waste of resources. This review aims to explore the characteristics of HTC-AP, identify the governing factors, and evaluate various valorization pathways to enable the utilization of HTC-AP. The review also proposes strategies to address the challenges in existing technologies for HTC-AP valorization and treatment, considering their merits and demerits. With the future prospects of valorizing HTC-AP, this review contributes to making HTC a more sustainable and economically viable process for waste management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrogen-doped magnetic porous carbons (M-NPCs) derived from COFs were prepared by direct carbonization. • Pyrolysis temperature has a significant impact on the porous structure and adsorption performance of M-NPCs. • The adsorption equilibrium of sulfamerazine over M-NPC was achieved within 2 min. • M-NPC can be easily recycled and its adsorption capacity toward SMR was 143 mg/g. The occurrence of sulfonamides in the water environment has garnered significant attention due to their potential adverse effects on ecosystems and human health. Despite this significance, effectively removing sulfonamides from polluted water sources remains a challenging task. In this study, a series of hierarchical magnetic porous carbon materials (M-NPC) doped with iron and nitrogen are prepared using a direct carbonization method, employing a covalent organic framework (COF) as a precursor. The resulting M-NPC exhibits a hierarchical structure, high porosity, and abundant N-containing binding sites, enabling efficient removal of sulfamerazine (SMR) within 2 min. Mechanism studies reveal that the adsorption of SMR by M-NPC followed the pseudo-second-order kinetic model (R 2 = 0.999) and the Freundlich model. Furthermore, electrostatic interactions, π-π stacking, and hydrogen bond interactions are identified as the dominant mechanisms contributing to excellent adsorption performance. Additionally, the M-NPC demonstrates easy operation and good regeneration ability, making it highly promising for the efficient removal of sulfonamides from wastewater. This development marks a significant advancement in addressing the challenge of removing sulfonamides from polluted water sources. [ABSTRACT FROM AUTHOR]