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BACKGROUND: Bacterial cellulose (BC) is a fiber substance produced by microbial fermentation. It is widely used in the food preservation industry because of its extremely pure texture, high crystallinity and high biocompatibility. In the present study, bacterial cellulose/thyme essential oil (BC/TEO‐E) with antibacterial and fresh‐keeping functions was prepared by ultrasonic treatment of modified bacterial cellulose for encapsulation of thyme essential oil, which effectively inhibited the spoilage of chilled chicken. RESULTS: The purified BC, produced by Acetobacter xylinum ATCC 53524, was ultrasonically treated wih different times (0, 30, 60 and 90 min). Transmission electron microscopy, scanning electron microscopy, Fourier transformed infrared spectroscopy, X‐ray diffraction, differential scanning calorimetry and zeta potential were used to characterize the structure of BC after ultrasound, showing that BC, treated for 30 min, had the optimal fiber structure, crystallinity (85.8%), thermal stability (347.77 °C) and solution stability (−26.63 ± 1.96 mV). BC/TEO‐E was prepared by a homogenizer for the preservation of chilled chicken. Optical microscopy indicated that the BC/TEO‐E prepared by 0.5% BC had optimal dispersion and stability, and even no delamination was observed in the emulsion. Compared with other groups (control, 0.5% BC and Tween‐E), the total number of colonies and coliforms in chilled chicken treated with 0.5% BC/TEO‐E was the lowest during the whole storage period (12 days), indicating that it can effectively inhibit bacterial growth. In addition, total volatile base nitrogen (TVB‐N), thiobarbituric acid reactive substances, pH and drip loss results showed that 0.5% BC/TEO‐E could effectively inhibit the spoilage of chilled chicken compared to the other treatment groups. CONCLUSION: All of the results acquired in the present study indicate that BC/TEO‐E has a potential application in chilled chicken preservation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Multifunctional electrocatalysts are desirable for overall water splitting and zinc-air batteries. In this work, N, S co-doped carbon nanotubes (CNT-NS) with a plentiful of defects were obtained through a novel molecular-level codoped and lattice defect construction method. Thiamine hydrochloride and thiocarbamide were adopted as new precursors in situ doping N and S into multi-walled CNTs surfaces, and lattice defects were constructed by in situ chemical etching using ammonium chloride and ammonium bicarbonate. These surface defects and N,S biatom co-doping synergistic effects can accumulate the CNT-NS to exhibit the superior behavior for electrocatalysis of water splitting and zinc-air batteries. The overpotential for overall water splitting was 1.61 V and the specific capacity for zinc-air batteries was 781 mA h g−1, which was superior to previous works. According to the Operando Raman spectroscopy measurements, the S atoms can serve as the intrinsic catalytic sites for HER and OER, and the defective CNT structures could enhance the catalytic kinetics by the electron-transfer process. Further, density functional theory (DFT) results also indicated the contribution of binary atoms co-doping for low ΔG H∗ values. Therefore, this work provides the valuable reference for rational design/construction for metal-free catalysts of overall water splitting. [Display omitted] • CNT-550-NS were successfully prepared through a molecular-level codoped and lattice defect construction method. • CNT-550-NS exhibited a plentiful of defective structure on the carbon nanotubes surfaces. • CNT-550-NS possessed a high contents of heteroatoms of N and S. • CNT-550-NS executed a remarkable performance for HER, OER and ORR. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials that are electrochemically bifunctional and active in supercapacitor and hydrogen-evolution-reaction (HER) applications have attracted recent research attention. We have prepared porous carbon spheres - doped Ni, Co - alloys by using a hydrothermal method with melamine and pectin as precursors and with the addition of nickel nitrate and cobalt nitrate. The corresponding materials exhibit good electrochemical performance and excellent electrocatalytic activity for HER. The overpotential (OP) of the as-prepared materials can achieve 240 mV keeping a Tafel slope (TS) of 55 mV dec−1 at 10 mA cm−2 in an acid (0.5 M H 2 SO 4) solution. The corresponding samples maintain stability after 24 h and 5000 cycles in the chronovoltage and cyclic voltammetry methods, respectively. When the as-prepared materials are oxidized by 30% H 2 O 2 for 12 h, the corresponding as-prepared oxidation samples exhibit excellent electrochemical performance in a supercapacitor application. The specific capacitance (SC) of the as-obtained materials reaches 312 F g−1 at 1 A g−1 with decent rate capability and cyclic stability. This work provides new applications for bifunctional electrochemically active materials. • A novel method is used in the preparation of porous spheres. • Porous spheres - coated Ni, Co - alloys structure were successfully obtained. • Shows Excellent HER performance in acidic environments. • Exhibits high specific capacitance in alkaline environments. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Carbon aerogels with excellent conductive characteristics and high specific capacitance have attracted more and more interests for next-generation energy storage applications. Three-dimensional interconnected Mn 2 O 3 /carbon aerogel supercapacitor electrodes are prepared by a novel doping method using MnO 2 coordinated by N, N-dimethylmethanamide (DMF). The coordinative MnO 2 (DMF/MnO 2) plays a key role in the sol-gel process of resorcinol and formaldehyde. The doped carbon aerogels exhibits a high specific surface area of 859 m2 g−1 and a good pore-size distribution of 10–15 nm. All of the doped carbon aerogels exhibit higher specific capacitance than pure carbon aerogels, and the highest specific capacitance (170 F g−1), at current density of 1.0 A g−1, is obtained in Mn–CA–5% when 5 mol% DMF/MnO 2 is added to the precursor solution. The specific capacitance is as high as 100 F g−1, at current density of 10.0 A g−1, and 97% of initial capacitance is retained over 1000 cycles at a current density of 5.0 A g−1. The doped carbon aerogels exhibits a high coulombic efficiency (up to 99.8%) and a good rate capability. The corresponding result is due to the novel doping method of DMF/MnO 2 addition. [ABSTRACT FROM AUTHOR]

Improving the specific capacitance of carbon aerogels in supercapacitors and maintaining their high specific surface area remained an important challenge. Here, we prepared resorcinol-phloroglucinol-formaldehyde carbon aerogels reduced with hydrazine hydrate by a microwave method. The effects of the amount of hydrazine hydrate and the time of microwave reaction on the electrochemical performance of carbon aerogels were investigated. The reductive carbon aerogels were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The XPS spectra of reductive carbon aerogels indicated a presence of four nitrogen N1s groups, three oxygen O1s groups and six carbon C1s groups in the deconvoluted spectra. Surface area analysis and electrochemical performance were also investigated. The results showed that the specific surface area of the N-doped carbon aerogels could be as high as 803 m2 g−1. According to the electrochemical testing results, the specific capacitance of the N-doped carbon aerogels significantly increased and reached 219 F g−1 at a current density of 1.5 A g−1 compared to the pristine carbon aerogels. The optimal dosage and time of hydrazine hydrate was 20.6 mol L−1 for 25 min. The N-doped carbon aerogels electrode exhibited excellent reversibility with a cycling efficiency of 93.6% after 10000 cycles. [ABSTRACT FROM AUTHOR]

Porous carbon xerogels were successfully fabricated by carbonization of resorcinol-formaldehyde-phloroglucinol gels in the presence of surfactants. The effect of non-ionic, cationic, anionic and zwitterionic surfactants on the porous structure of carbon xerogels was investigated. Micropore structural carbon xerogels were obtained when a cationic surfactant was used. The result of surface tension test showed the non-ionic surfactant Tween 60 gave the lowest surface tension. Thermal conductivity experiments revealed the carbon xerogels in this work possessed low thermal conductivity and are suitable as thermal insulation materials. The pore size directly determined the thermal conductivity of carbon xerogels, and the thermal conductivity decreased with pore size. Among the obtained samples, the one using hexamethylenetetramine (HTM) exhibited the highest CO 2 adsorption capacity (2.89 mmol g −1 ) and adsorption selectivity as a result of the high microporosity (88.0%). Therefore, HTM-CA was identified as a promising material for CO 2 adsorption. [ABSTRACT FROM AUTHOR]

Carbon aerogels of an inter-connected three-dimensional (3D) structure are a potential carbon material for supercapacitors. We report a new oxidation modification method to prepare a series of modified carbon aerogels (OM-CA) by Hummers oxidation method. Oxidation-modified carbon aerogels (OM-CA) are obtained from carbon aerogel powders oxidized by Hummers method. Sulfuric acid stoichiometry is studied in order to investigate the effect of the surface oxygen group on surface area and electrochemical performance. Additionally, heteroatoms are doped into carbon aerogels in the oxidation process. The effect of heteroatom doping on electrochemical performance as a supercapacitor electrode material is investigated. When the amount of sulfuric acid is 40 wt%, the dopping manganese content is 0.9 mol%, the specific surface area of OM-CA is 450 m 2 /g, and its specific capacitance is 151 F g −1 at 0.5 A g −1 , which is achieved by heteroatom doping and texture properties. In addition, OM-CA composite supercapacitors exhibit a stable cycle life at a current density of 0.5 A g −1 and retain 98.0% of initial capacitance over 500 cycles, and OM-CA-40% still presents a higher capacity, up to 148 F g −1 at 0.5 A g −1 . The high specific surface area and specific capacitance suggest the porous carbon material has potential applications in supercapacitors. [ABSTRACT FROM AUTHOR]

Heteroatom doping in carbon aerogels is critical for improving the surface areas and electronic properties of these aerogels. This paper demonstrates doping sulfur (S) atom into carbon aerogels. S-doped carbon aerogels (S-CAs) were prepared via a sol-gel process using phloroglucinol (P), resorcinol (R) and formaldehyde as the polymerization precursors with sodium carbonate (Na 2 CO 3 ) as the basic catalyst and sodium 4-hydroxybenzenesulfonate (HBS) as the surfactant. The as-synthesized products were dried in normal temperature and carbonized with temperature-programmed. The effects of S-doping on the surface area and electronic properties of the S-CAs were studied by a surface area analyzer and electrochemical workstation. When the S loading was up to 1.38%, the corresponding S-CA exhibited the most optimal surface area and specific capacitance. The textural properties were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), a surface area analyzer, an X-ray diffraction spectrometer, a Raman spectrometer, the X-ray photoelectron spectroscopy (XPS) spectra, an elemental analyzer and an EDX detector, and the electrochemical properties were measured using cyclic voltammetry, galvanostatic charge–discharge measurements and electrochemical impedance spectroscopy (EIS). When the molar ratio of HBS/(P + R) was 0.05, the S loading was 1.38%, the specific surface area of the as-synthesized CA was 831 m 2 /g, and its specific capacitance was 105 F/g. [ABSTRACT FROM AUTHOR]

MicroRNA (miR)-34a was recently determined to contribute to the pathological development of Alzheimer’s disease (AD). miR-34a deficiency significantly attenuates cognitive deficits in amyloid precursor protein (APP)/presenilin 1 (PS1) mice; however, its role in early AD pathology and the underlying mechanisms remain elusive. Here, we confirmed that the increase of miR-34a expression in APP/PS1 mice was earlier than the relevant AD pathological characteristics, such as amyloid-β production, amyloid plaque deposition, and cognitive deficits. Furthermore, because predicted miR-34a target genes were broadly linked to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N -methyl- d -aspartate (NMDA) receptors, we evaluated synaptic plasticity by investigating high-frequency conditioning tetanus-induced excitatory postsynaptic potential, which revealed that synaptic plasticity was promoted in miR-34a knockout/APP/PS1 mice. Therefore, we assessed the expression of the presynaptic components synaptophysin and postsynaptic density protein 95 (PSD95) and found that synaptophysin and PSD95 were not altered by miR-34a deficiency. Additionally, the synaptic strength (vesicular fusion, vesicular docking, and transporting) was either not significantly changed. We also evaluated the levels of AMPA and NMDA receptors, which showed that the expression of AMPA and NMDA receptors was markedly upregulated in APP/PS1 mice with miR-34a deficiency. We conclude that miR-34a is involved in synaptic deficits in AD pathological development, which was, at least in part, due to the inhibition of NMDA (by miR-34a-5p) and AMPA (by miR-34a-3p) receptor expression. [ABSTRACT FROM AUTHOR]

The influence of metals on the structure and performance of carbon aerogels is presented here. Metal-doped carbon aerogels (M-CA) were obtained by a simple in situ method without any catalyst. The physical properties were characterized by SEM, XRD, Raman spectroscopy, XPS, and N 2 adsorption-desorption. The results show that the addition of metal particles did not destroy the original 3D structure of carbon aerogels, and Ni-CA displayed excellent pore size distribution and a high degree of graphitization. The results of the electrochemical performance revealed nickel doped carbon aerogel (Ni-CA) gave the highest specific capacitance (126.6 F g − 1 ) at 1 A g − 1 because of the suitable pore size distribution and high conductivity. A cycling performance test showed good cycle stability of all the M-CA in this study, and the attenuation of Ni-CA after 1000 cycles was the lowest recorded, at only 0.6%. [ABSTRACT FROM AUTHOR]

Developing robust and efficient non noble catalysts for water splitting is needed in the energy storage and application field. Constructing electronic structures to enhance the catalytic activity is always interesting and meaningful. Herein, electronic structures are simply synthesized through a rational design of Co-Co 0.85 Se heterostructures anchoring on the defective N-doped carbon matrix. Co anchoring on the defective N-doped carbon matrix is obtained from hydrothermal-carbonization process of pectin, melamine and cobalt chloride. Rational design of partial selenization can construct electronic structures to form Co-Co 0.85 Se heterostructures anchoring on the defective N-doped carbon matrix (Co-Co 0.85 Se-CN). The introduction of Co atoms induces the electron cloud redistribution of Co 0.85 Se, enhancing the electrocatalytic activity for water splitting. The defective N-doped carbon matrix provides plenty of catalytic sites and good conductivity for ions transition. Co-Co 0.85 Se-CN exhibits outstanding catalytic performance for hydrogen evolution reaction and oxygen evolution reaction. The Operando Raman spectroscopy demonstrates that the dual active centers of Co and Se atom, facilitating the catalytic process for water splitting. DFT calculation results reveal that the constructed electronic structures from Co and Co 0.85 Se-CN is good for the H* adsorption for HER. This work provides a facile synthetic strategy to construct electronic structures for water splitting. [Display omitted] • Co-Co 0.85 Se loading defective porous carbon matrix successfully prepared through a facile method. • Co-Co 0.85 Se-CN exhibits a plentiful of defects and a specific electron structure. • Co-Co 0.85 Se-CN executes a remarkable performance for HER and OER. [ABSTRACT FROM AUTHOR]

Metal phosphides are usually being utilized for hydrogen evolution electrocatalysts with enormous potential. Meanwhile, the heterostructure can enhance the catalytic performance for hydrogen evolution reaction (HER). Inspired by the recent preparation of efficient catalysts for HER by using heterogeneous structures of different metal phosphides, we have designed a simple two-step method strategy based on sol-gel/carbonization to prepare the bimetal phosphide coated by nitrogen and phosphorus codoped (N,P-codoped) porous carbon. Phytic acid, chitosan and aniline are adopted to form the N,P-codoped porous carbon framework, the ferric chloride (FeCl 3) and ammonium molybdate tetrahydrate (H 8 MoN 2 O 4) are used as the metal sources to obtained bimetal phosphides (MoP/FeP). The heterostructural interface between the bimetal phosphides of MoP/FeP enhance the catalytic performance, while the N,P-codoped porous carbon promotes the development of reaction kinetics to accelerate the mass and electron transition. The prepared catalysts display limited overpotentials at high current density and exhibit good stability for long-time test. Density functional theory (DFT) is adopted to investigate the interact between the bimetal phosphides, which proves that the heterostructural interface can reduce the reaction Gibbs free-energy (△G H*) and benefit the adsorption / desorption of intermediate H*. This work provides a facile route to the design of the metal phosphides for HER. [Display omitted] • Prepared MoP/FeP coated by N,P-codoped porous carbon via simple method. • Heterostructural interface between MoP/FeP enhance the catalytic performance. • Prepared catalysts display a superior catalytic activity for HER. • Density functional theory prove the heterostructural interface actions. • Provides new idea for the preparation of multifunctional bimetal phosphide. [ABSTRACT FROM AUTHOR]

Porous biomass-carbon materials for supercapacitor applications have recently attracted attention. Chitin, which has abundant amides and hydroxyl groups, was used as an ideal precursor for carbon in this work. The chitin was treated with a one-step method to produce a heteroatom-loaded porous carbon material, and its electrochemical properties were significantly improved through the introduction of loaded elements. A mixture of chitin, zinc chloride, and heteroatoms was carbonized to obtain heteroatoms (N and S) and the bimetallic sulfide loaded hierarchical porous carbon. Then, the porous carbon with S, N, Zn, and Fe heteroatoms loading was used to prepare a supercapacitor with a specific capacitance of 277.4 F g−1 at 1 A g−1. In addition, the supercapacitor had a specific capacitance retention rate of 90% at 5 A g−1 after 10,000 cycles. Therefore, hierarchical porous carbon materials loaded with heteroatoms and bimetallic sulfide were prepared by carbonization activation with chitin as the precursor. The resulting supercapacitor showed that the as-prepared porous biomass materials possessed ideal charging-discharging performance. Moreover, this work provides strategies for obtaining metal sulfides and heteroatom co-loading of carbon materials with excellent properties using a simple and efficient one-step method for renewable energy storage device applications. • Porous carbon doped with nitrogen, iron, zinc and sulfur is rationally obtained from biomass chitin through one-step preparation/activated method. • Porous carbon exhibits a large specific surface area and a specific capacitance. • New finding in excellent electrical properties of the novel design is revealed. • Porous carbon are assembled into super capacitors to light LEDs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Develop new molybdenum compounds (Mo 2 C, MoP and MoS 2) nanoclusters supported on N-doped reduced graphene oxide. • Prepared catalysts exhibit excellent and durable electrocatalytic performance over a broad pH range. • Potential applications of ordered self-assembled composites for water splitting to produce hydrogen. Electrocatalytic water splitting for hydrogen production is highly desirable to replace oil energy. The catalytic performance is closely related to the conductivity, active sites and reaction Gibbs free energy of the catalyst. A general guideline for improving catalytic performance is to obtain porous carbon-based materials with a high surface area, plentiful defects and metal compound loading. Here, defect-rich nitrogen-doped reduced graphene oxide (RGO) with molybdenum (Mo)-based compound loading was designed through a two-step method. The peroxide-assisted step under low-temperature carbonization with an air atmosphere promotes the formation of defects, and the hydrothermal process improves the crosslinking degree to form a porous structure at a high carbonization temperature. The obtained catalysts exhibit excellent and durable electrocatalytic performance over a broad pH range. In addition, the transmission electron microscopy (TEM) and electron paramagnetic resonance (EPR) results clearly reveal the presence of defects. The theoretical analysis demonstrates that the RGO and Mo-based compounds have an efficient synergetic effect on the catalytic activity. This work provides clues for the development of new catalysts for water splitting to produce hydrogen. [ABSTRACT FROM AUTHOR]

d-cysteine (d-cys) has been demonstrated to possess an extraordinary antibacterial activity because of its unique steric configuration. However, inefficient antibacterial properties seriously hinder its wide applications. Here, cysteine-functionalized gold nanoparticles (d-/l-Au NPs) were prepared by loading d-/l-cysteine on the surface of gold nanoparticles for the effective inhibition of Escherichia coli (E. coli) in vitro and in vivo, and the effects on the intestinal microflora in mice were explored during the treatment of E. coli infection in the gut. We found that the antibacterial activity of d-/l-Au NPs was more than 2–3 times higher than pure d-cysteine, l-cysteine and Au NPs. Compared with l-Au NPs, d-Au NPs showed the stronger antibacterial activity, which was related to its unique steric configuration. Chiral Au NPs showed stronger destructive effects on cell membrane compared to other groups, which further leads to the leakage of the cytoplasm and bacterial cell death. The in vivo antibacterial experiment illustrated that d-Au NPs displayed impressive antibacterial activity in the treatment of E. coli-infected mice comparable to kanamycin, whereas they could not affect the balance of intestinal microflora. This work is of great significance in the development of an effective chiral antibacterial agent. [ABSTRACT FROM AUTHOR]

Given its clean energy and absence of exhaust gases, hydrogen is an ideal candidate for energy demand. Electrochemical hydrogen evolution reaction (HER) have attracted increasing attention, and non-precious metal compounds have been considered as next-generation catalysts to replace the traditional Pt-based catalysts in this reaction. This study adopts a novel sol-gel method of chitosan and formaldehyde to prepare an N-doped carbon matrix with Nickel phosphide (Ni 2 P) and Molybdenum phosphide (MoP) loading. Phytic acid is used as the P source to dissolve chitosan. The interface between Ni 2 P and MoP in the as-prepared catalysts facilitates HER with an excellent stability in a wide pH universal solution. The onset potentials of the catalyst are 300, 200, and 5 mV in 0.5 mol L−1 sulfuric acid, 1.0 mol L−1 phosphate buffer solution, and 1.0 mol L−1 potassium hydroxide, respectively, and the corresponding Tafel slopes are 63, 99, and 64 mV dec−1. Density functional theory is adopted to support the experiment. Results suggest that the synergistic effect from the interface can obviously reduce the hydrogen adsorption free energy to benefit the adsorption/desorption. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) have been increasingly found to fulfill key functions in neurodegenerative diseases. This study aimed to probe the function of lncRNA MALAT1 in neuronal recovery in Alzheimer's disease (AD). Aβ25-35 was used to induce AD in a rat model and neuronal injury in PC12 and C6 cells. Aberrantly expressed lncRNAs/microRNAs (miRNAs) in AD rats were screened out by microarray analyses. Altered expression of MALAT1, miR-30b and CNR1 was performed to explore their roles in neuronal recovery in rat and cell models. Consequently, LncRNA MALAT1 and CNR1 were poorly expressed while miR-30b was highly expressed in Aβ25-35-induced rat models and cells. Overexpression of MALAT1 or CNR1 reduced neuronal injury in rat hippocampus. It increased viability and decreased apoptosis in injured PC12 and C6 cells, and decreased the secretion of pro-inflammatory factor IL-6 and TNF-α but increased IL-10 production. However, overexpression of miR-30b reversed these trends. MALAT1 could served as a sponge for mR-30b to up-regulate CNR1 expression. The phosphorylation of PI3K and AKT was stimulated when MALAT1 or CNR1 was overexpressed. To sum up, we found MALAT1 could promote neuronal recovery following AD through the miR-30b/CNR1 network and the PI3K/AKT signaling activation. [ABSTRACT FROM AUTHOR]

Electrochemical hydrogen evolution has become a popular way to produce clean energy. Traditional catalysts (e.g. platinum (Pt)) are very expensive and rare; therefore, environmentally friendly and cost-effective catalysts are being widely developed. Here, molybdenum carbide and metallic nickel supported on a N-doped porous carbon matrix are prepared as an electrocatalyst through a one-step hydrothermal method with the addition of melamine, polyvinylpyrrolidone (PVP), pectin, ammonium molybdate and nickel nitrate, and the catalysts exhibit excellent catalytic performance for electrochemical hydrogen evolution. The catalysts created with a carbonization temperature of 1000 °C display a low onset overpotential of 60 mV in an acidic solution with a small Tafel slope of 64 mV dec−1 and low overpotentials of 170 mV and 220 mV in 0.5 M H 2 SO 4 and 1.0 M KOH, respectively, at 10 mA cm−2. The obtained catalyst maintains remarkable stability after a 240 h durability test and 10000 cyclic voltammetry cycles. The obtained materials possess excellent catalytic performance for the HER due to the synergistic effect of nickel incorporation into molybdenum carbide and the benefit of the porous N-doped carbon matrix for electron and H∗ transport. [ABSTRACT FROM AUTHOR]

Microporous carbon xerogels (CXs) were successfully fabricated via a facile one-pot strategy using eutectic salt mixture (KCl and ZnCl 2) as dual activator and catalyst. Their pore structures, morphology, and selective CO 2 adsorption behaviors were thoroughly studied by varying the contents of eutectic salt mixture. The presented CXs herein showed excellent CO 2 adsorption selectivities, and the CX-4 with optimum salt concentration (12.9%) exhibited the highest CO 2 adsorption capacity of 4.39 mmol g−1 at 273 K, which was ascribed to their special microscopic pore structure. Compared with the reported carbon materials, the optimum CX-4 exhibits a comparable or superior CO 2 adsorption performance under similar conditions, showing great potential for efficient CO 2 capture and separation from flue gas and natural gas. [ABSTRACT FROM AUTHOR]

• Develop new self-assembled Ni/Co phosphides composite spheres. • Carbon nanospheres via a hydrothermal process and effective manner. • Exhibit excellent HER electrocatalytic activity. • Significant potentials in composite electrocatalyst design. Because of their high catalytic activity and abundant resources, nonprecious transition metal phosphides are favorable substitutes for noble metals as hydrogen evolution reaction (HER) electrocatalysts. In this work, self-assembled Ni/Co phosphide composite N-doped carbon spheres were successfully prepared via a hydrothermal process, which had abundant exposed active sites for the HER. The as-obtained samples exhibited excellent electrocatalytic activity for the HER with an overpotential of only 160 mV (vs. RHE) at a current density of 10 mA cm−2 in a 0.5 M H 2 SO 4 solution and a comparatively low Tafel slope (57 mV dec−1). Additionally, the Ni 2 P/CoP spheres also show good stability after 120 h and 5000 cycles of a cyclic voltammetry test. Their highly efficient catalytic activity for the HER is attributed to the specific spherical structure, which provides exposed Ni 2 P and CoP for favorable adsorption and desorption of hydrogen. Therefore, nonprecious transition metal phosphide spheres may provide a promising strategy to improve the catalytic activity of HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Spectral preprocessing techniques can, to a certain extent, eliminate irrelevant information, such as current noise and stray light from spectral data, thereby enhancing the performance of prediction models. However, current preprocessing techniques mostly attempt to find the best single preprocessing method or their combination, overlooking the complementary information among different preprocessing methods. These preprocessing techniques fail to maximize the utilization of useful information in spectral data and restrict the performance of prediction models. This study proposed a spectral ensemble preprocessing method based on the rapidly developing ensemble learning methods in recent years and the ridge regression (RR) model, named stacking preprocessing ridge regression (SPRR), to address the aforementioned issues. Different from conventional ensemble learning methods, the proposed SPRR method applied multiple different preprocessing techniques to the original spectral data, generating multiple preprocessed datasets. These datasets were then individually inputted into RR base models for training. Ultimately, RR still served as the meta-model, integrating the output results of each RR base model through stacking. This approach not only produced diversity in base models but also achieved higher accuracy and lower computational complexity by using a single type of base model. On the apple spectral dataset collected by our team, correlation analysis showed significant complementary information among the data produced by different preprocessing techniques. This provided robust theoretical support for the proposed SPRR method. By introducing the currently popular averaging ensemble preprocessing method in a comparative experiment, the results of applying the proposed SPRR method to six datasets (apple, meat, wheat, olive oil, tablet, and corn) demonstrated that compared to the single preprocessing method and averaging ensemble preprocessing method, SPRR yielded the best accuracy and reliability for all six datasets. Furthermore, under the same conditions of the training and test datasets, the proposed SPRR method demonstrated better performance than the four commonly used ensemble preprocessing methods. [Display omitted] • RR, with high accuracy and fast training, was used as base models for stacking. • Complementary information carried by different preprocessed datasets was certified. • Stacked RR models built on diverse preprocessed data enhanced prediction performance. • 2000 iterations showed exceptional prediction of SPRR across six datasets. • The SPRR method was compared with four commonly used ensemble preprocessing methods. [ABSTRACT FROM AUTHOR]

We prepared a series of modified carbon aerogels with oxygen-containing functional groups through a sol–gel process by polycondensation of phloroglucinol, resorcinol and formaldehyde using starch addition. The effect of starch addition on the pore structure and electrochemical performance of the carbon aerogels was investigated. Carbon aerogels were characterized by scanning-electron microscopy, transmission-electron microscopy, surface-area analysis, X-ray diffractometry, Raman spectrometry and X-ray photoelectron spectroscopy. The electrochemical properties were studied by using cyclic voltammetry, galvanostatic charge–discharge measurements and electrochemical impedance spectroscopy. When the starch addition was 25 wt%, the as-prepared sample had a specific surface area of 734 m2 g−1 and an outstanding specific capacitance of 147 F g−1 at 1.0 A g−1. The as-prepared carbon aerogels exhibited a high coulombic efficiency and a stable cycle life at a current density of 1.0 A g−1 over 1000 cycles. This ideal performance was attributed to the addition of starch, which was beneficial for the application of carbon aerogels in supercapacitors. • A novel method is used in the preparation of carbon aerogels. • Starch/phloroglucinol-resorcinol-formaldehyde carbon aerogels are subsequently applied in supercapacitors. • Oxygen-containing surface groups contribute to higher capacity and cycling performance. [ABSTRACT FROM AUTHOR]

In the present study, nanoscale rod-shaped manganese oxide (MnO) mixtures were successfully prepared from graphitic carbon nitride (C3N4) and potassium permanganate (KMnO4) through a hydrothermal method. The as-prepared MnO nanomixtures exhibited high activity in the adsorption and degradation of methylene blue (MB). The as-synthesized products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), surface area analysis, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Furthermore, the effects of the dose of MnO nanomixtures, pH of the solution, initial concentration of MB, and the temperature of MB removal in dye adsorption and degradation experiments was investigated. The degradation mechanism of MB upon treatment with MnO nanomixtures and H2O2 was studied and discussed. The results showed that a maximum adsorption capacity of 154 mg g−1 was obtained for a 60 mg L−1 MB solution at pH 9.0 and 25 °C, and the highest MB degradation ratio reached 99.8% under the following optimum conditions: 50 mL of MB solution (20 mg L−1) at room temperature and pH ≈ 8.0 with 7 mg of C, N-doped MnO and 0.5 mL of H2O2. [ABSTRACT FROM AUTHOR]

Environmental problems caused by metal ions have caused widespread concern in recent years. In this work, carbon aerogels (CAs) adsorbing different metal ions were prepared. The adsorption performance and kinetics of metal ions (Cu(II), Cr(VI), and Fe(III)) on carbon aerogels were systematically investigated. The results indicated that the maximum adsorption capacity of Cu(II) was 424 mg·g−1 in 600 mg·L−1 copper solution. Adsorption performances of Cu(II), Cr(VI), and Fe(III) on CAs well fitted with a pseudo-second-order kinetic model. The structures and morphologies of metal-containing samples were characterized by scanning electron micrographs (SEM), Energy Dispersive Spectrometer (EDS), transmission electron microscope (TEM), and X-ray diffraction (XRD). The results demonstrated that the texture and electrochemical performance of CAs adsorbing metal ions exhibited a clear change. The specific surface area of CAs for adsorbing copper ions was 450 m2·g−1 and they showed a small average pore diameter (7.16 nm). Furthermore, CAs adsorbing metals could be used for the super capacitor. The specific capacitance of CAs adsorbing copper ions could reach 255 F·g−1 at a current density of 1.0 A·g−1. The CA-Cu electrode materials exhibited excellent reversibility with a cycling efficiency of 97% after 5000 cycles. [ABSTRACT FROM AUTHOR]

Biomass-based carbon aerogels hold promising application prospect in the field of supercapacitors. In this research, starch was selected as a raw material for preparing carbon aerogels. The preparation process of starch hydrogels was simplified by using KOH, which can change starch suspension into hydrogels at room temperature. Moreover, the molecular mixing of KOH and starch was realized, so that KOH can be fully utilized in the activation process. The specific surface area of the starch-based carbon aerogels prepared by this method was 1349 m2/g, and the proportion of micropores was 43.7 %. Remarkably, as electrode materials for supercapacitors, the starch-based carbon aerogels exhibited outstanding electrochemical performance. In a three-electrode system, the carbon aerogels exhibited specific capacitance of 211.5 F/g at 0.5 A/g and 138.5 F/g at 10 A/g, suggesting their suitability for high-current applications. In a symmetrical supercapacitor configuration, the materials exhibited an energy density of 11.3 Wh/kg at a power density of 0.5 kW/kg and the specific capacitance can maintain 98.91 % after 10,000 cycles. Overall, this work provides a new method for mixing activators, which will foster potential advances in starch based carbon aerogels. • The preparation of starch-based carbon aerogels was simplified by adding KOH. • The molecular mixing of KOH and starch was realized, which significantly improved the activation effect of KOH. • The starch-based carbon aerogels exhibited a specific surface area of 1349 m2/g. • The proportion of micropores can be adjusted by the amount of KOH added • The starch-based carbon aerogels exhibited excellent electrochemical performance as electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNT) are potential electrode materials for supercapacitors due to their high specific surface area and excellent conductivity. Here, 1,4-Naphthoquinone (NQ)-modified nitrogen-oxygen co-doped carbon nanotubes (NQ/N–O-CNT) were synthesized. The influences of NQ modification on the structure and electrochemical properties of as-prepared materials were examined by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron microscopy (XPS), scanning electron microscopy (SEM), galvanostatic charge/discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). By the modification process, nitrogen and oxygen were effectively doped into CNT, causing an increase in nitrogen- and oxygen-containing functional groups, which was proved by XPS and FTIR. The effective debundling of CNT and the presence of densely packed globular structures on the surface of individual nanotubes was confirmed by SEM. And benefited from the reversible redox reaction of NQ, the specific capacitance of NQ/CNT composites can reach up to 143.68 F g−1, which is 4.5 times higher than that of CNT (25.78 F g−1), demonstrating quinone organic compounds can serve as a sustainable pseudocapacitor material for high-performance supercapacitors. After 3000 cycles, the specific capacitance is still 83.6% of its original value. Image 1 • 1,4-Naphthoquinone modified nitrogen-oxygen co-doped carbon nanotubes (NQ/N–O-CNT) were synthesized. • The characterization confirmed 1,4-NQ was successfully anchored on the CNT by covalent bonds. • After modification, the specific capacitance of the CNT composites increased by 4.5 times based on the redox reaction of NQ. [ABSTRACT FROM AUTHOR]

Traditional carbon aerogels are made of resorcinol and formaldehyde. The synthesis process is cumbersome and the electrochemical performance is poor. Therefore, designing carbon aerogels with environmentally friendly raw materials, simple synthesis steps and good electrochemical performance is of great important. In this article, Cu-doped carbon aerogels (Cu-CA) were synthesized by one-step carbonization using sodium alginate (SA) as the carbon precursor. The specific surface area of the Cu-CA was 230.4 m2 g−1. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to obtained the microstructure of the Cu-CA. Cu nanoparticles (Cu NPs) were found to be embedded in the carbon aerogels homogeneously. The performances of the Cu-CA as supercapacitor electrode materials were investigated via cyclic voltammetry test (CV), galvanostatic charge-discharge test (GCD) and electrochemical impedance spectroscopy (EIS) using three-electrode system and the reference electrode was Hg/HgO electrode. Due to the metal-doped and unique hierarchical porous structure, the specific capacitance of the Cu-CA was up to 414.4 F g−1 with GCD (scan rate: 0.3 mV s−1), and the Cu-CA electrode showed good cycling stability. The excellent electrochemical performances of the Cu-CA indicate their great potential applications in the energy storage field. Image 1021 • The Cu-doped carbon aerogels (Cu-CA) were prepared by one-step carbonization method using sodium alginate. • Cu nanoparticles (Cu NPs) are firmly embedded in the carbon aerogels. • The Cu-CA exhibit a specific capacitance of 414.4 F g−1 at 0.3 mV s−1. [ABSTRACT FROM AUTHOR]

Carbon aerogels (CA) with uniform pore structures were prepared by the polycondensation of phloroglucinol, resorcinol, and formaldehyde, using carboxylated chitosan as a soft template. The CA were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and surface area analysis. When carboxylated chitosan was added, the time for wet gel formation was reduced by 60%, and the CA showed a more uniform pore structures. The electrochemical performance of the CA was measured in a three-electrode electrochemical cell. The CA prepared with added carboxylated chitosan showed lower charge transfer resistance on the electrode surface, and the specific capacitances were also enhanced, showing a specific capacitance as high as 135 F/g at a resorcinol-to-carboxylated chitosan mass ratio of 250:1 at a current density of 0.5 A/g. This specific capacitance is much higher than that of the CA without carboxylated chitosan. The capacitance retention under increasing discharge current density was also enhanced by the addition of carboxylated chitosan. The electrochemical performance of the CA in different electrolytes (1 M LiOH, 1 M NaOH, 1 M KOH, 3 M KOH, 6 M KOH, and 9 M KOH) was investigated. The results show that the electrochemical performance in 6 M KOH was better than those in other electrolytes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large-area porphyrin-COF nanofilm is formed by the interfacial polymerization. • Co2+/IL co-modification can provide additional interface and pseudocapacitance. • Flexible MSC-IL-Co-COF TAPP-DHPA exhibits high capacitive properties. Large-area Co2+/ionic liquid (IL) co-modified porphyrin-COF nanofilm was prepared by the chelation Co2+ ions on porphyrin-N and grafting IL on –OH groups in COF TAPP-DHPA skeleton respectively. This IL-Co-COF TAPP-DHPA self-supporting film can directly customized into interdigital electrodes, and assembled as flexible MSC-IL-Co-COF TAPP-DHPA devices. The MSC-IL-Co-COF TAPP-DHPA device exhibits the good energy storage properties, such as the high energy density of 67.2 mWh/cm3 at 3.46 W/cm3, good cycling stability with capacitance retention of 91 % after 5,000 cycles. These outstanding performances can be explained by the fact that the chelated Co2+ ions can provide the additional Faradaic redox reaction, and grafted long-chain IL can improve the charge accumulation capacity by pore channel segmentation and growing adsorbing H+ active sites. Notably, the MSC-IL-Co-COF TAPP-DHPA owns the high anti-bending property, allowing for bending at different angles. This work can broaden the COF film application prospects in flexible, wearable electronic devices. [ABSTRACT FROM AUTHOR]

Infrared and visible image fusion (IVIF) aims to preserve thermal radiation information from infrared images while integrating texture details from visible images. Thermal radiation information is mainly expressed through image intensities, while texture details are typically expressed through image gradients. However, existing dual-discriminator generative adversarial networks (GANs) often rely on two structurally identical discriminators for learning, which do not fully account for the distinct learning needs of infrared and visible image information. To this end, this paper proposes a novel GAN with a heterogeneous dual-discriminator network and an attention-based fusion strategy (GAN-HA). Specifically, recognizing the intrinsic differences between infrared and visible images, we propose, for the first time, a novel heterogeneous dual-discriminator network to simultaneously capture thermal radiation information and texture details. The two discriminators in this network are structurally different, including a salient discriminator for infrared images and a detailed discriminator for visible images. They are able to learn rich image intensity information and image gradient information, respectively. In addition, a new attention-based fusion strategy is designed in the generator to appropriately emphasize the learned information from different source images, thereby improving the information representation ability of the fusion result. In this way, the fused images generated by GAN-HA can more effectively maintain both the salience of thermal targets and the sharpness of textures. Extensive experiments on various public datasets demonstrate the superiority of GAN-HA over other state-of-the-art (SOTA) algorithms while showcasing its higher potential for practical applications. • A heterogeneous dual-discriminator generative adversarial network is proposed. • Two different discriminators are built to meet distinct information learning needs. • Discriminators integrate diverse attention modules to focus on respective images. • An attention-based fusion strategy is designed to merge the learned information. [ABSTRACT FROM AUTHOR]

Drug-resistant bacterial infections exhibit a major threat to public health. Thus, exploring a novel antibacterial with efficient inhibition is urgently needed. Herein, this paper describes three types of MSNs (MSNs-FC2-R1, MSNs-FC2-R0.75, MSNs-FC2-R0.5) with controllable pore size (4–6 nm) and particle size (30–90 nm) that were successfully prepared. The MSNs were loaded with tetracycline hydrochloride (TCH) for effective inhibition of Escherichia coli (ATCC25922) and TCH-resistant Escherichia coli (MQ776). Results showed that the loading capacity of TCH in three types of MSNs was as high as over 500 mg/g, and the cumulative release was less than 33% in 60 h. The inhibitory rate of MSNs-FC2-R0.5 loaded with TCH against E. coli and drug-resistant E. coli reached 99.9% and 92.9% at the concentration of MIC, respectively, compared with the other two types of MSNs or free TCH. Modified MSNs in our study showed a great application for long-term bacterial growth inhibition. [ABSTRACT FROM AUTHOR]

Biomass-based carbon aerogels have attracted significant research attention due to the wide range of raw material, low cost, and environmental friendliness. In this study, green and sustainable carbon aerogels have been prepared using starch as raw material. Potassium chloride and potassium carbonate have been selected as template and activator. Due to the joint action of potassium chloride and potassium carbonate, the starch-based carbon aerogels exhibit a specific surface area of 2367 m2 g-1 with ant-hole-like 3D network pore structure. The starch-based carbon aerogels have been further employed as the electrode material for supercapacitors. The specific capacitance of the carbon aerogels is 292.3 and 245 F g-1 at current densities of 1.0 and 10 A g-1, respectively. In addition, the starch-based carbon aerogels demonstrate excellent sorption ability for oil and organics as well as insignificant sorption ability for H 2 O, thus, indicating their potential use as optimal oil-water separation material. [ABSTRACT FROM AUTHOR]

Nitrogen-rich melamine-based carbon nanosheets were prepared through via polyvinyl pyrrolidone/ammonia chloride-mediate strategy. [Display omitted] • Nitrogen-rich melamine-based carbon nanosheets was synthesized and characterized. • The pseudo-second-order model and Langmuir model fitted the adsorption process. • The maximum adsorption capacity of NCG-2 for MB was 348.2 mg g−1. • The adsorption process of MB were endothermic and spontaneous. The removal of the methylene blue (MB), a cationic azo dye, in water is highly demanded due to its harmful effects on human health. In this study, the nitrogen-doped carbon nano-sheet was prepared as the adsorbent for MB using the efficient one-pot pyrolysis of melamine in the presence of NH 4 Cl and PVP. During the heat-treatment, the PVP interacted with melamine forming hydrogen-bond, which would not only elevate the melamine deamination process but also prohibit the melamine polymerization, which led to the formation of the layered structure. The addition of NH 4 Cl in the pyrolysis mixture would favor the formation of crumpled graphene-like-structure. The prepared materials showed a very high adsorption capacity of MB (348.2 mg/g), which is much higher than many other materials. Such a high adsorption capacity was likely due to its unique graphene-like structure, high N doping with a high content of pyridinic N and graphitic N, and large specific surface area. Moreover, the material was successfully recycled with only a slight decrease in the removal efficiency after 5 cycles. [ABSTRACT FROM AUTHOR]

Supercapacitors are promising for high power application in the recent years. In particular, the conversion of simple and available carbon materials into economic and high performance electrical devices receives excellent scientific and technological interest. This paper reports a one-step strategy for synthesizing hierarchical porous carbon derived from phenolic resin (PR), which is then used to configure electric double-layer capacitors (EDLCs). Here, a carbon material with a flexible porous structure, large specific surface area, and high graphitization degree is prepared using potassium ferrate (K 2 FeO 4) to catalytically activate PR and to realize synchronous carbonization and graphitization. This method overcomes the disadvantage of time-consuming, high-cost, and environmentally unfriendly. In addition, the as-prepared carbon material has a high specific surface area (1086 m2 g−1) and a large pore size (3.07 nm), which can increase the transfer rate of electrolyte ions. The specific capacitance of the obtained electrode material is 315 F g−1 at 1.0 A g−1, and the optimized electrode material has an ultra-long cycle lifetime (capacitance retention rate is 96.3% after 10,000 cycles). Thus, the hierarchically Fe-doped porous carbon material derived from PR material is expected to realize high rate capacitance for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Carbon aerogels with low cost and eco-friendly are considered as ideal electrode materials for supercapacitors. In this investigation, nitrogen self-doped carbon aerogels (NSCA) are prepared by microwave hydrothermal and high-temperature carbonization using chitin as carbon and nitrogen sources. Zinc chloride is used as a dehydration agent and an activator. Owing to the low boiling point of Zinc chloride, it does not require any additional steps to remove the activator. Also, due to the activation of Zinc chloride, the specific surface area of NSCA reaches 2540 m2 g−1. In the three-electrode system, NSCA-1000 exhibits specific capacitance of 249.4 and 164.9 F g−1 at current densities of 1.0 and 10 A g−1, respectively. In the two-electrode system, the NSCA-1000 based symmetrical supercapacitor demonstrates an energy density and power density of 26.15 Wh kg−1 and 0.95 kW kg−1 at 1.0 A g−1, respectively. Meanwhile, NSCA-1000 displays excellent cycling stability that the specific capacitance can maintain 98.44% after 15,000 cycles at a current density of 2.0 A g−1. Image 1 • Nitrogen doped carbon aerogels (NSCA) with high specific surface area were prepared. • No additional steps are required to remove the activator. • NSCA show a specific capacitance of 249.4 F g−1 and good cycling stability. [ABSTRACT FROM AUTHOR]

Electrochemical catalytic water splitting process is a potential method for clear hydrogen production. The interfacial electron regulation engineering is an effective path to prepare electrochemical catalysts for water splitting process. Herein, we obtain Ni doping molybdenum-based phosphides with heterojunction interface through a facile method. The acquired Ni doping molybdenum-based phosphides loading on N-doping porous carbon (MoNiP-MoP-PNC) exhibits a high specific surface area (SA), an abundant of porous structure and a electron regulation heterojunction interface. The high SA expose more catalytic sites and the plentiful of pores accelerate the electron/mass transfer, and the electron regulation heterojunction interface can induce the P-orbital electron redistribution to facilitate the adsorption/ desorption (ads/des) of [H] intermediate. The MoNiP-MoP-PNC shows a good catalytic behavior with a low overpotential and an excellent catalytic stability in 1.0 M KOH solution. The synchrotron-radiation results verify the interfacial electron regulation effect that the P -orbital of Mo atom is changed by the adjacent Ni atom and P atom. Meanwhile, density functional theory (DFT) theoretical calculation unmasks that the heterojunction interface can regulate the electron distribution to accelerate the HER. This work indicates a simple route to develop interfacial electron regulation engineering for high effective catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

Construction of heterojunction inside a catalyst can induce electron redistribution with optimization of adsorption and desorption with [H] and [O] intermediates , attributed to accelerate HER and ORR process. In this work, we designed novel catalysts for HER and ORR by structuring a coralloidal morphology and controlling the synthetic process. The polyphosphazene framework was built via hexachlorocyclotriphosphazene (HCCP) polymerization, which was used as the metal–organic framework (MOF) particle supporter. The polyphosphazene framework was beneficial for the growth of MOF particles with a coralloidal morphology, which exposed catalytic active sites. The polyphosphazene framework provides an abundance heteroatom of nitrogen and phosphorus that modulate the electron density of the metal for catalytic process. The coralloidal catalysts exhibited a versatile catalytic behavior for HER. In 0.1 M KOH, the ORR half-wave potential (HWP)of CoP@PNC (0.85 V) was higher to Pt/C (0.82 V). In 1.0 M KOH, MoP/CoMoP-1 @PNC had a good HER catalytic performance, and the overpotential at 10 mA cm−2 was 82 mV. DFT calculations demonstrate that multimetal phosphides can provide a heterojunction interface, thereby regulating the electron density for the catalytic reaction. This work provides a novel route to prepare high-efficiency catalysts by conjointly structuring the micromorphology and heterojunction interface. [Display omitted] • MP@PNC exhibited a good conductivity and a high element content of N and P; • Multi-metal phosphide heterojunction induced charge redistribution to facilitate catalytic reaction; • CoP@PNC executed a remarkable performance for ORR; • MoP/CoMoP-1 @PNC executed excellent catalytic properties for HER. [ABSTRACT FROM AUTHOR]

An N-doped carbon/CuO-Fe 2 O 3 (NC-CuFe) nanocomposite was successfully prepared via a simple, green one-pot annealing method. Different techniques were employed to characterize the physical and chemical properties of the prepared products, such as the composition, texture, structure and reducibility. XRD, XPS, TPR and especially TEM demonstrated the formation of CuFe 2 O 4 in the Cu-doped composite. All the Cu-doped materials (NC-CuFe) showed higher activity in the Fenton reaction of MB degradation than the non-doped sample (C-Fe). In particular, the composite doped with 10 wt% CuO (NC-CuFe-2) exhibited the best performance, with approximately 98% of the methylene blue (MB) removed in 180 min in the presence of H 2 O 2. The high specific surface area, the mutual charge interaction between Cu2+ and Fe3+, the mobility of the lattice oxygen and the high pyridinic N content in NC-CuFe-2 were responsible for the high activity in the Fenton reaction. Moreover, NC-CuFe-2 also demonstrated excellent stability and reusability, which were crucial for practical applications. Schematic illustration of the fabrication process of NC-CuFe-2 and Fenton-reaction for MB degradation. Image 1 • The novel N-doped carbon/CuO-Fe 2 O 3 were fabricated by one-pot annealing method. • The novel N-doped carbon/CuO-Fe 2 O 3 exhibited an grape-like structure. • The N-doped carbon/CuO-Fe 2 O 3 display good catalytic performance and reusability. [ABSTRACT FROM AUTHOR]

The Ti 3 C 2 T x MXene is a new class of two-dimensional inorganic material, which can be used as anticorrosive filler for epoxy coating. In this work, the BTA molecules are intercalated into Ti 3 C 2 T x MXene through hydrogen bonding to obtain a high-performance active-passive dual protective function Ti 3 C 2 T x MXene@BTA composite corrosion inhibitor. The morphology, structure and composition of prepared Ti 3 C 2 T x MXene@BTA nanocomposite were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectrometer (XPS). Moreover, the release behavior and inhibition behavior were investigated by UV–vis spectrophotometer and electrochemical impedance spectroscopy (EIS), respectively. The results show that the continuously released of BTA can be achieved by introducing BTA into Ti 3 C 2 T x MXene interlayer, and the complete release time can reach 1000 min. In addition, EIS results show that the Ti 3 C 2 T x MXene@BTA composite coating exhibited the excellent anti-corrosion properties, and the impedance value remains above 1010 Ω·cm2 for 50 days in 3.5 NaCl solution, which is 4 orders of magnitude higher than that of pure epoxy coating. [Display omitted] • BTA was firstly intercalated into Ti 3 C 2 T x MXene by hydrogen bonding. • Ti 3 C 2 T x MXene@BTA combines physical barrier and active anti-corrosion. • Composite coating exhibits good anticorrosion and certain self-healing property. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • develop new electrospun composite materials via SVA treatment. • self-assembled composite prepared in an eco-friendly and effective manner. • composite exhibits high-efficient catalytic capacities and good stability. • significant potentials in self-assembled composite films design. Abstract A new ternary poly(ε-caprolactone) (PCL)/poly(ethylene oxide) (PEO)@AuNPs composite material with high catalytic activity and favorable structural stability has been successfully prepared. The prepared PCL/PEO composite fibers by electrospinning have been treated with an easy-to-operate solvent vapor annealing (SVA) process, demonstrating wrinkled fiber nanostructures, promoting the significantly high specific surface area and more active sites in the surface of electrospun fiber. Then NaBH 4 was used as a reducing agent to reduce HAuCl 4 to form gold nanoparticles, resulting in the targeted PCL/PEO@AuNPs composite material. The obtained PCL/PEO@AuNPs composites demonstrated potential catalytic ability and good reusability in the catalytic reduction of 4-nitrophenol and 2-nitroaniline systems, showing promising and wide applications in catalytic composite materials and self-assembled films. [ABSTRACT FROM AUTHOR]

Hierarchical N-doped porous carbons were synthesized using a self-templated and solvent-free assembly approach via directly heating green polyaspartic acid potassium. The samples prepared under different calcining temperatures were characterized, which exhibited the structural features of high pore volume (0.88–1.75 cm3/g) and large specific surface area (1592–3133 m2/g). Subsequently, these samples were applied for selective CO 2 capture and supercapacitor electrodes. The N-PCM-900 prepared at 900 °C afforded superb electrochemical performance, including extremely large specific capacitance (346 F/g at 1 A/g), high-rate capability (charge-discharge profiles at 20 A/g), and excellent cycle stability (96.86 % retention after 1000 cycles) in KOH electrolyte (6 M). Moreover, N-PCM-900 simultaneously provided high CO 2 adsorption ability (4.63 mmol/g) at 273 K, and high ideal adsorption solution theoretical value (25) for capturing CO 2 /N 2 at 298 K. The multifunctional porous carbon presented herein exhibited great potential for electrochemical energy storage and gas adsorption/separation. [Display omitted] • A self-templated and solvent-free assembly approach was developed for the synthesis of hierarchical N-doped porous carbon. • The samples exhibited the structural features of high pore volume (1.75 m3 g) and large specific surface area (3133 m2 g). • High specific capacitance (161 F/g) and stability (99.4 % after 1000 cycles) are obtained. • Excellent CO 2 adsorption capacity (4.21 mmol/g) at 273 K and IAST selectivity (25) are gave. [ABSTRACT FROM AUTHOR]

The hierarchical porous nitrogen-doped two-dimensional carbon (HNGC) was prepared by simple calcination of magnesium sulfate (MgSO 4) and self-synthesized nitrogen-doped two-dimensional graphene-like carbon at a mild temperature in oxygen. The influence MgSO4 on the morphology, structure and chemical composition of the prepared HNGC samples were studied using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy, surface area analysis, X-ray photoelectron microscopy and elemental analyzer. HNGC-2 exhibited a uniform three-dimensional coral-like porous inter-connected structure, large specific surface area, high pore volume, and no loss of nitrogen content. HNGC-2 demonstrated an excellent rate capability of 62.8% at 20 A g−1, outstanding stability of 96.1% following 5000 cycles and the assembled symmetric supercapcitor achieved 12.5 Wh kg−1 at a 350 Wkg-1 and 7.5 Wh kg−1 at 3500 Wkg-1. The novel method was also found to be effective for facilitating the electrochemical performance of commercial biomass active carbon. In addition, HNGC-2 was used for the photo-catalytic degradation of methylene blue and over 99% of methylene blue was successfully degraded under 25-min visible irradiation in the presence of potassium persulfate. The enhanced electrochemical performance and the excellent photo-catalytic performance of HNGC-2 indicated that porous carbon can be successfully activated using an appropriate oxidation strategy. The illustration for the formation of the hierarchy porous structure of HNGC materials. [Display omitted] • Hierarchical porous nitrogen-doped carbon was prepared by a novel strategy. • The influence of Magnesium sulfate was systematically studied and discussed. • The strategy can greatly enhance the photo-catalytic and electrical performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The energy storage mechanisms of electric double-layer supercapacitors are presented. • Several commonly used supercapacitor carbon electrode materials are shown. • Prospects for further research and development of the supercapacitor carbon materials. The role of supercapacitors in the energy storage industry is gaining importance due to their high power density and long life cycle. In recent years, supercapacitors have made numerous breakthroughs. Carbon materials are the most commonly used electrode materials for supercapacitors and the researches of carbon materials are significant for developing supercapacitors. Herein, this article presents the energy storage mechanisms of supercapacitors and the commonly used carbon electrode materials. The energy storage mechanism includes commonly used energy storage models and the verification and in-depth understanding of these models using molecular dynamic simulation and in-situ technology. The carbon electrode materials section introduces the most commonly used carbon materials and their applications in the field of supercapacitors. Finally, the development trend of carbon-based supercapacitors is prospected. [ABSTRACT FROM AUTHOR]

In this study, a 3D Fe-based and N-doped coral-like carbon composite (Fe-NGLC) was successfully prepared via the simple impregnation of a self-made 3D nitrogen-enriched and porous layered graphene-like support with Fe 2 (SO 4) 3 as the precursor. It was characterized through X-ray diffractometry, scanning electron microscopy, X-ray photoelectron spectroscopy, etc.; Fe-NGLC exhibited regular three-dimensional coral-like structures with dense porosity and high of Fe–N species content. As a heterogeneous Fenton catalyst of the methylene blue (MB) degradation, the prepared composite showed impressive activity over a wide pH range (4–10). Almost 100% of the MB could be degraded in 60 min, and the results agreed well with the pseudo-first-order kinetic model. To identify the crucial active sites of MB degradation, the correlation between the rate constant derived from the pseudo-first-order kinetic model and the different Fe species in the catalyst prepared under various conditions was investigated. This revealed the key role of the Fe–N complexes for the heterogeneous Fenton reaction. Moreover, Fe-NGLC exhibited recyclability and only a slight decrease in removal efficiency after five cycles. The excellent performance of Fe-NGLC demonstrates its great potential as a Fenton catalyst for wastewater treatment. Schematic illustration of the preparation of Fe-NGLC and catalytic process of MB degradation [Display omitted] [ABSTRACT FROM AUTHOR]

The preparation method of porous carbon traditionally involves many steps and requires inert atmosphere resulting in time-consuming and high-cost. We reported a simple and easy method of N-doped micro/meso porous carbon (NPC) via a one-step carbonization of polyvinylpyrrolidone, melamine and ammonium chloride in air. The influences of PVP mass and carbonization temperature on surface group function, the morphology, microstructure and pore distribution of NPC samples were studied by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy and surface area analysis. The thermal behavior of NPC was analyzed by thermogravimetric analysis coupled to Fourier transform infrared spectroscopy. Moreover, the electrochemical performances of the as-prepared NPC samples were measured by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The micro/meso pores and high content of pyridine-N and quaternary-N endowed NPC samples with high capacitive performance and long cyclic life. The specific capacitance of the prepared NPC sample could reach as high as 215.9 F g−1 at 1 A g−1 and 89.5 F g−1 even at 10 A g−1. Especially, the symmetric supercapacitor assembled by NPC-3-900 achieved 13.2 W h kg−1 at 350 W kg−1 and excellent cyclic performance (91.4% after 10,000 GCD circles). [Display omitted] • NPC was successfully prepared from heating PVP, melamine and NH 4 Cl in air. • The preparation method is simple, easy and simple-facility. • The preparation mechanism is illustrated clearly. [ABSTRACT FROM AUTHOR]