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Constructing electrode materials with greation transfer ability, highly porous, and good electrical conductivity is of significance for realizing high-performance electrochemical double-layer capacitors. Here, the N-PC (N-doped porous carbon)/HWCF (hollow wooden carbon fiber) composites that have all the features were synthesized, which was obtained from carbonization of the mixture of hollow wood fiber (HWF)/ZIF-8 and pore-forming substances. It was found that ZIF-8 nanoparticles are closely packed forming a uniform ZIF layer fully covering the external surface of WF by the electrostatic interaction. They were converted into the inter-connect N-PC network anchoring on the HWF surface after calcination, which provided a continuous conductive network for electrons. The resulting N-PC/HWCF-based electrodes exhibited impressive electrochemical performance. The specific capacitance of N-PC/HWCF-800 is 121 F/g at a current density of 0.5 A/g with excellent cycling stability over 10000 cycles. Furthermore, the symmetrical supercapacitors (SSCs) with two N-PC/HWCF-800 electrodes delivered an encouraging energy density of 4.8 Wh kg−1when the power density is as high as 3600 W/kg. This study provides insights for the design of hierarchical porous carbon structure towards next-generation high-power smart devices.

The classical distributed hybrid flow shop scheduling problem (DHFSP) only considers static production settings while ignores operation inspection and reprocessing. However, in the actual production, the manufacturing environment is usually dynamic; and the operation inspection and reprocessing are very necessary to avoid unqualified jobs from being transported to other production units and to make reasonable arrangements for unqualified and unprocessed jobs. In this paper, we propose a DHFSP with operation inspection and reprocessing (DHFSPR) for the first time, in which the operation inspection and reprocessing as well as the processing time and energy consumption are considered simultaneously. An improved memetic algorithm (IMA) is then designed to solve the DHFSPR, where some effective crossover and mutation operators, a new dynamic rescheduling method (DRM) and local search operator (LSO) are integrated. A total 60 DHFSPR benchmark instances are constructed to verify the performance of our IMA. Extensive experiments carried out demonstrate that the DRM and LSO can effectively improve the performance of IMA, and the IMA has obvious superiority to solve the DHFSPR problem compared with other three well-known algorithms. Our proposed model and algorithm here will be beneficial for the production managers who work with distributed hybrid shop systems in scheduling their production activities by considering operation inspection and reprocessing.

• A novel holly-leaf shaped graphene (HLG) with unique hollowed-out structure has been designed. • A possible formation mechanism of HLG has been demonstrated that strong capillary forces from wood arrayed pore structure plays a crucial role. • Both experiment and theoretical model demonstrate its structural superiority in facilitating photothermal conversion. • HLG/wood has excellent performance for seawater desalination and sewage treatment. Similar to transpiration, the formulation of interfacial solar evaporation has been designed to perform water treatment. The concept involves wood-based support (tree) with a graphene-based layer acting as leaves. To enhance light absorption and solar-thermal conversion capacity, a novel holly-leaf graphene (HLG) layer with an individual hollowed-out structure was engineered. The formation mechanism of this HLG was shown to be linked to the strong capillarity forces in the polyporous wood. By creating biomimetic leaves made of graphene, the light-to-heat conversion performance can be improved, while exhibiting substantially lower thermal conductivity (0.074 W/(m K)) than natural wood. Under solar irradiation, HLG/wood exhibits an outstanding evaporation rate of 1.96 kg/(m2 h), with an impressive efficiency of 94.2 %. A theoretical model of HLG/wood based on the thermal management capability was built to further confirm its structural superiority in facilitating photothermal conversion. Consequently, a bilayer evaporator based on HLG/wood has the potential to revolutionize water purification processes, including desalination of seawater, removal of heavy metal ions, and treatment of organic dye-contaminated wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Graphical abstract: Boosting the catalytic ability of MoS2is vital to its further application as a class of promising non-noble catalysts to address environmental issues. Benefiting from the O-doping-induced electronic effect and interfacial coupling and synergistic effect between MoS2and reduced graphene oxide (rGO), the as-prepared O-MoS2&rGO heterogeneous catalyst exhibits enhanced degradation efficiency for methylene blue (MB) dye.

Graphical abstract: A new hybrid supercapacitor with excellent electrochemical performance is fabricated by electrostatic hetero-assembly of positively charged 1D KCu7S4and negatively charged 2D titanium carbide (Ti3C2) MXene.

Metal–organic frameworks (MOFs) have received great attention in environmental remediation application. In particular, one-dimensional (1D) MOF materials have excellent catalytic degradation performance because of their extraordinary surface–volume relationship, unique interface and surface structure characteristics, and high surface area. Nevertheless, an effective, simple, and environment friendly method to fabricate 1D MOF materials is very important for their large-scale application, especially in environmental treatment with strict cost requirements. Herein, two kinds of 1D MOF composites (HNTs/ZIF-67 and HNTs/MIL-88A) could be fabricated controllably by using natural halloysite nanotube (HNT) minerals via in situ growth induced by electrostatic adsorption. The typical morphological characteristic of HNTs/ZIF-67 is its mulberry shape with ZIF-67 nanoparticles being grown on the surface of HNTs, while HNTs/MIL-88A is rice-shaped in which the introduced HNTs affect the growth size of HNTs/MIL-88A remarkably. Furthermore, the solar-Fenton catalytic performances and mechanisms of the HNTs/ZIF-67 and HNTs/MIL-88A composites are investigated. The results indicate that the HNTs/ZIF-67 and HNTs/MIL-88A composites could remarkably degrade methylene blue in peroxymonosulfate (PMS) and H2O2systems under solar light, respectively. The active species capture experimental data, and electron paramagnetic resonance determinations reveal that HNTs/ZIF-67 in the PMS system could be excited to mainly generate SO4–•radicals and HNTs/MIL-88A in the H2O2system could be excited to mainly generate •OH radicals. This work provides a simple and effective strategy to construct high-efficiency 1D MOF catalysts based on cheap, easily available, and eco-friendly HNT materials. It would also greatly promote the low-cost and large-scale application of MOF materials in environmental treatment.

Metal-organic frameworks (MOFs), composed of metal ions and organic linkers, have garnered enormous attention in catalytic application due to their exceptional characteristics such as high specific surface area, low density, large porosity and structural diversity. However, the recycling and performance improvement of MOF should be taken into account in material design. In this work, we fabricated copper-doped metal-organic framework/wood aerogel composites to enhance the activation of peroxymonosulfate (PMS) for the degradation of organic contaminants. Wood Aerogel (WA) was used as suitable carrier to solve the recycling problem, and copper-doped ZIF-67 was developed to enhance the catalytic performance. Copper-doped ZIF-67 (ZIF-67B) was loaded into the cavities of a wood aerogel by in situwet chemical precipitation, followed by freeze drying to obtain the composite. The effects of copper doping ratio, temperature, catalyst dosage, initial pH and other operational parameters on the degradation of organic pollutants were comprehensively investigated. The catalytic capacity of ZIF-67B@WA (CoxCu(1-x)) was investigated by activating PMS for the removal of Rhodamine B (RhB). The results demonstrate that the degradation efficiency of ZIF-67B@WA (CoxCu(1-x)) towards RhB can achieve 100 % within 15 min, showing exceptional catalytic performance compared with ZIF-67@WA. Even after four consecutive cycles, the degradation efficiency remains at 87.5 %, indicating that the catalyst has good cycle stability. Additionally, possible degradation mechanisms are proposed in this study, in which WA provides high loading active site/area for MOF catalyst and Cu doping can accelerate electron transfer and facilitate the redox cycling of Co2+and Co3+, thereby enhancing catalytic efficiency. This work expands the application scope of MOF materials in environmental remediation and holds promising prospects.

Magnetically recyclable and self-propulsive micron carbon fiber (CF) immobilizing Fe3O4nanoparticles with favorable solar-Fenton catalytic activity were successfully prepared by a combined twostep method. In the first step, CF was synthesized from waste paper and subsequently modified by mussel-inspired polydopamine (PDA) with biomimetic adhesion function and highly active functional groups. In the second, well-dispersed Fe3O4nanoparticles were fabricated and anchored on the surface of the PDA modified CF. The solar-Fenton catalytic performance and reusability for the composites were fully evaluated. The results show the degradation rate of the prepared catalyst for methylene blue (MB) in a free agitating process reached 97.8% after 80 min under simulated Sunlight. After 10 repetitive catalytic cycles, the degradation rate for MB could maintain above 95% meanwhile the magnetic properties of the catalyst remained strong indicating good recovery of the catalyst after the reaction. The possible degradation mechanism of MB is also discussed. It indicates that hydroxyl radicals play an important role in the catalytic degradation reaction, while hole trapping and superoxide radical are beneficial to the enhancement of decolorization efficiency of MB.

Hard carbon (HC) is a promising anode material for sodium-ion batteries. However, the intrinsic relationship between the closed pores/surface groups and sodium storage performance has been unclear, leading to difficulties in targeted regulation. In this study, renewable tannin extracts were used as raw materials to prepare HC anodes with abundant tunable closed pores and carbonyl groups through a pyrolytic modulation strategy. Combining ex situ characterizations reveals that closed pores and carbonyl groups are regulated by the pyrolytic process. Further, it is demonstrated that the plateau region is mainly contributed by the closed pores; highly stable fluorine-rich solid electrolyte interphase compositions are produced through carbonyl-induced interfacial catalysis. The optimized HC anode displays good cycling stability, exhibiting a high reversible capacity (360.96 mAh g−1) at 30 mA g−1and capacity retention of up to 94% after 500 cycles at 1 A g−1. Moreover, the full battery assembled with Na3V2(PO4)3/C demonstrates a stable cycling performance. These findings provide a fresh knowledge of the structural design of high-performance HC anode materials and the mechanism of sodium storage in HC.

In the present work, a Pd/graphene/cordierite (Pd/Gr/Cor) composite was prepared as a monolithic catalyst for low-temperature combustion of toluene. We mainly focused on understanding the role of graphene coating through investigation of catalytic performance and adsorption behavior of the composite. Compared with the traditional Pd/Cor catalyst without graphene coating, Pd/Gr/Cor catalyst delivered much higher activity and stability for toluene catalytic combustion in both dry and moist conditions. Transmission electron microscopy (TEM) and hydrophobic characterizations indicated that graphene coating can considerably improve the dispersity of Pd nanoparticles and enhance the hydrophobicity of the cordierite support. The adsorption behavior of the above two catalysts, including adsorption isothermal, adsorption kinetics, and adsorption thermodynamics were carefully investigated. The simulation results indicated that a large amount of toluene was adsorbed on graphene surface through relatively weak interaction, whereas only a relatively small amount of toluene was adsorbed on Pd surface with strong affinity. The adsorption thermal calculation indicated that the adsorption of toluene on graphene was a process with reduced entropy, indicating highly-ordered assembly of toluene molecular on graphene. It is the significant concentration and affinity gap between graphene and Pd that ensures a simultaneously and rapid transfer of toluene during the reaction process.

We report here a g-C3N4-coated activated carbon as the support for Pd catalysts and investigate the effect of nitrogen species in g-C3N4on the dispersity and stability of Pd.

Recycling of spent lithium-ion batteries (LIBs) has attracted increasing attentions recently on account of continuous growth demand for corresponding critical metals/materials and environmental requirement of solid waste disposal. In this work, rice husk as one of the most abundant renewable fuel materials in the world was used to prepare rice husk char (RC) and applied to recycle multivalent ions in waste water from hydrometallurgical technology dispose of spent LIBs. Rice husk char with specific surface area and abundant pores was obtained via pickling and desilication process (DPRC). The structural characterization of the obtained rice husk char and its adsorption capacity for multivalent ions in recycled batteries were studied. XRD, TEM, SEM, Raman, and BET were used for the characterization of the raw and the modified samples. The results show rice husk chars after desilication has more flourishing pore structure and larger pore size about 50–60 nm. Meanwhile, after desilication, the particle size of rice husk char decreased to 31.392 μm, and the specific surface area is about 402.10 m2/g. Its nitrogen adsorption desorption curve (BET) conforms to the type IV adsorption isotherm with H3 hysteresis ring, indicating that the prepared rice husk char is a mesoporous material. And the adsorption capacity of optimized DPRC for Ni, Co, and Mn ions is 7.00 mg/g, 4.84 mg/g, and 2.67 mg/g, respectively. It also demonstrated a good fit in the Freundlich model for DPRC-600°C, and a possible adsorption mechanism is proposed. The study indicates biochar materials have great potential as an adsorbent to recover multivalent ions from spent batteries.

Micropores and defects, like oxygen-containing groups, as active sites for sodium-ion storage in hard carbon have attracted considerable attention; nevertheless, most oxygen doping or oxidizing processes inevitably introduce undesired oxygen groups into a carbon framework, leading to deteriorated initial Coulombic efficiency (ICE). Here, precise carbonyl groups and closed micropores are together introduced into biomass-derived hard carbon to enhance the Na-ion storage performance. The hard carbon delivers a large reversible capacity of 354.6 mA h g–1at 30 mA g–1, a high ICE (88.7%), as well as ultra-long cycling stability (277 mA h g–1at 0.3 A g–1over 1000 cycles; 243 mA h g–1at 1 A g–1over 5000 cycles). The rate capability and cycling stability of hard carbon in carbonate- and diglyme-based electrolytes are contrasted to demonstrate the superiority of diglyme. Cyclic voltammetry at varied scans and galvanostatic intermittent titration techniques are carried out to clarify the disparity between the two different electrolyte systems. Furthermore, the as-prepared hard carbon is utilized as the anode for sodium-ion full cells exhibiting an energy density of 166.2 W h kg–1at 0.2 C and a long-cycle life (47.9% retention over 200 cycles at 1 C).