Chemical activation is extensively employed in the preparation of porous carbon materials. However, this conventional approach suffers from several drawbacks: it is toxic, chemically caustic, environmentally unfriendly, and often costly. To overcome these limitations, a green and facile self-template activation strategy was developed for synthesizing Chitosan Hydrochloride-derived porous carbons (CHCs), the optimized porous carbon CHC-N4-K1, prepared via activation with organic salts potassium citrate under sol-gel assistance, not only displayed a high specific surface area of 2473.98 m2/g and a large pore volume of 1.82 cm3/g, but also demonstrated outstanding performance in methylene blue (MB) adsorption and CO2 capture. For MB adsorption, approximately 99% removal efficiency can be achieved within 15 min when the initial MB concentration is 100mg/L, and the adsorption capacity reached 703 mg/g. The adsorption mechanism involved electrostatic interactions, pore filling, and π-π stacking. For CO2 capture, CHC-N4-K1 exhibited adsorption capacities of 5.38 mmol/g at 273 K and 4.42 mmol/g at 298 K under 1 bar. It also demonstrated a high CO2/N2 selectivity (>24) and maintained 98% after 10 consecutive adsorption-desorption cycles, indicating efficient regeneration. Surface charge distribution and adsorption energy (Ead) calculated by density functional theory (DFT) confirmed the synergistic effect between the well-developed pore structure and hydroxyl/nitrogen-containing functional groups. This work establishes an effectively strategy to activation of porous carbon materials for CO2 capture and wastewater treatment.

The utilization of biomass resources can not only alleviate energy shortage and environmental problems, but also contribute to sustainable development. The preparation of carbon aerogel from biomass can realize the efficient utilization of waste resources. Herein, this review summarizes the preparation and application of biomass based carbon aerogel. Firstly, this review systematically deconstruct the intrinsic molecular architectures and chemistry of quintessential biomass feedstocks (cellulose, chitin, starch, and sodium alginate) and elucidate how these inherent features dictate the gelation pathways, pore structure evolution, and ultimate functionality of the resulting carbon skeletons. Then, this review further advances beyond a conventional listing of applications in water treatment, energy storage, electromagnetic interference shielding, gas adsorption, thermal insulation, and sensing. This review provides a focused analysis on the mechanistic links between the tailorable hierarchical porosity/surface chemistry of biomass CAs and their performance. Finally, critical challenges hindering industrial translation are identified, including the absence of a dominant high-performance precursor, low carbonization yield, and the energy-intensive freeze-drying bottleneck. This review aims to provide a foundational framework and a forward-looking design logic for transitioning biomass based carbon aerogel from laboratory curiosities toward customizable, high-performance materials for advanced sustainable technologies.

In this study, N-doped graphene-like activated carbon (NGAC) catalysts with tailored nitrogen configurations and comparable specific surface areas were fabricated via magnesium oxide (MgO) dosage modulation. When the mass ratio of MgO to raw carbon was controlled at 1:1, mesopores and macropores were well developed, ensuring sufficient exposure and high-density distribution of active sites. Consequently, the resulting NGAC-2 removed 98.7% of norfloxacin and mineralized 57.8% of total organic carbon (TOC) within 60 min, alongside excellent recyclability and stability. Integrated experimental and theoretical analyses revealed a dual-function mechanism: pyridinic-N and pyrrolic-N served as adsorption sites for NOR enrichment, while graphitic-N functioned as the primary active site for peroxydisulfate (PDS) activation due to its optimal adsorption energy profile (higher for NOR, lower for PDS). DFT calculations demonstrated that C6 atom within pyridinic structure maybe donate maximum electron density to PDS, implying its important role in singlet oxygen generation via superoxide radicals recombination. Crucially, competitive adsorption creates a steric sheltering effect that enhances graphitic-N's advantage in mediating the dominant NGAC-PDS* electron transfer pathway. This work provides fundamental insights into designing high-efficiency carbon catalysts with spatially separated adsorption-activation sites for emerging contaminant removal.

The development of cost-effective and durable oxygen reduction reaction (ORR) catalysts is crucial for advancing proton exchange membrane fuel cells (PEMFCs). PtFe alloy catalysts have emerged as a key research focus. However, weak interactions between conventional carbon supports and transition metals lead to metal dissolution, severely compromising catalytic durability. To address this, we constructed a hierarchical porous nitrogen-doped carbon support (LC) via template-assisted pyrolysis, and subsequently synthesized highly dispersed PtFe/LC catalysts using a reduction approach involving hydrogen calcination. This strategy effectively suppresses nanoparticle agglomeration while anchoring metal particles through Fe-N bonds, significantly mitigating transition metal leaching. In acidic media, the optimized catalyst demonstrates a remarkable half-wave potential of 0.92 V (vs. RHE), outperforming commercial Pt/C (0.87 V).

The dewaterability of wastewater sludge by the solid waste of iron-mud (IM)/carbon (IMS) composite prepared via the in-situ carbothermal reduction method was systematically studied in this paper. It investigated the effects of different IMS materials, IM dosages and stirring speeds on sludge dewaterability, including water content (WC), capillary suction time (CST), extracellular polymeric substances (EPS) contents and particle size. The results of dewatering tests demonstrated that IMS materials significantly enhanced sludge dewaterability, resulting in a reduction of 39.85% in CST and 13.26% reduction in WC in the dewatered sludge under optimum condition (IMS-3 dosage of 8 % dry solids; stirring speed of 250 r/min for 30 min). Electron paramagnetic resonancec (EPR) and scavenging experiments were conducted to better understand the dewatering process mechanism. This results indicated that both hydroxyl radicals (center dot OH) and superoxide radicals (center dot O-2(-)) collaborate during the dewatering process. Furthermore, analysis were performed on the particle size of sludge flocs and scanning electron microscopy (SEM) imaging of sludge morphology to reveal the synergistic effects of IMS treatment. A two-step mechanism involving oxidation and Fe(III)-based re-flocculation maybe explain the synergistic effect of IMS treatment. This novel recycle-based IMS composite approach offers a new management strategy for industrial solid wastes while enhancing the sludge dewatering efficiency.

Biomass carbon aerogels are widely used as electrode materials for supercapacitors due to high specific surface area, excellent conductivity, low cost, and environmental friendliness. However, the electrochemical performance of biomass carbon aerogels decrease significantly at high power. Herein, starch-based carbon aerogels with microsurface wrinkles are designed in this study. Starch hydrogels are rapidly prepared by using the property that KOH/KCl can gelatinize starch at room temperature. During high-temperature carbonization, the molten salt that is formed by KOH and KCl gives the starch-based aerogels (KCA-KCl) a porous structures with a high specific surface area (2014 m2/g) and microsurface wrinkles. The porous structures and the microsurface wrinkles enables the material to maintain good electrochemical performance at both low and high power. When it is used as electrode material for supercapacitors, the specific capacitance of KCA-KCl is 246.0 F/g at a current density of 1.0 A/g and the capacitance retention of 10 A/g for KCA-KCl is 77.9 % in three electrode system. In two electrode system, KCA-KCl exhibited an energy density of 14.72 Wh/kg at a power density of 0.5 kW/kg and the specific capacitance can maintain 96.33 % after 10,000 cycles. This study provides a feasible strategy to prepare high-performance electrode materials for supercapacitors.

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.

Carbon materials are valuable for adsorbing CO 2 . In this work, carbon materials with large specific surface area and pore volume were prepared through the combination of sodium alginate and zinc chloride, were applied to adsorb CO 2 at 273 K and 298 K, showing a large adsorption capacity 2.75 mmol g -1 and 2.19 mmol g -1 , respectively. Zinc chloride acts as an activator and pore forming agent.

Carbon aerogel (CA) is a new type of lightweight porous material with many excellent properties. Here, CAFe-PPy was prepared via iron and conductive polymer polypyrrole (PPy) on carbon aerogel. The physical properties of CA and CAFe-ppy were compared. Iron, nitrogen and oxygen were successfully loaded onto CAFe-PPy. PPy can increase the conductivity of CAFe-PPy, but it also blocks some holes.

Multifunctional electrocatalysts are desirable for overall water splitting and zinc-air bat-teries. 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 batte-ries. 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 cat-alytic kinetics by the electron-transfer process. Further, density functional theory (DFT) results also indicated the contribution of binary atoms co-doping for low DGH* values. Therefore, this work provides the valuable reference for rational design/construction for metal-free catalysts of overall water splitting.(c) 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

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 cm(3)/g) and large specific surface area (1592-3133 m(2)/g). Subsequently, these samples were applied for selective CO2 capture and supercapacitor electrodes. The N-PCM-900 prepared at 900 degrees 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 CO2 adsorption ability (4.63 mmol/g) at 273 K, and high ideal adsorption solution theoretical value (25) for capturing CO2/N-2 at 298 K. The multifunctional porous carbon presented herein exhibited great potential for electrochemical energy storage and gas adsorption/separation. (c) 2022 Published by Elsevier B.V.

Background: Thus, the excellent electrochemical property of PR-Fe@MnO2 composite made it an encouraging electrode material for practical applications like charge storage and in other pseudocapacitors.Methods: Using phenolic resin (PR) as a carbon source, potassium ferrate (K2FeO4) and manganese acetate (Mn(CH3COO)2 cent 4H2O) as the dopants, a one-step carbonization method was used to prepare a series of Fe3O4 and MnO2 co-doped composites, which are denoted as PR-Fe@MnO2. During high-temperature carbonization (800 degrees C), partially amorphous carbon forms a multi-layer graphene structure, making PR-Fe@MnO2 exhibit a high degree of graphitization. After doping, the transition metal Mn was investigated theoretically by performing density functional theory calculations.Significant Findings: The results confirmed that doping of moderate Mn ions in the PR-Fe lattice improved the interactions between OH- in the electrolyte and Mn metal center, consequently, the electrical conductivity (19%) of the electrode according to the equivalent series resistance (Rs). The Mn composition also increased the specific area for more electroactive sites and reduced the charge transfer resistance (decreased by 27.7%). As a result, PR-Fe@MnO2-1.5 had the highest specific capacitance of 601 F/g at 1.0 A/g and superior cycling stability (capacitance retention of 97.8% after 10,000 cycles). Furthermore, the assembled PRFe@MnO2-1.5//PR-Fe@MnO2-1.5 symmetric supercapacitor provided a specific energy density of 25.7 Wh/ kg at a power density of 384.9 W/kg.(c) 2022 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

The hierarchical porous nitrogen-doped two-dimensional carbon (HNGC) was prepared by simple calcination of magnesium sulfate (MgSO4) 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 per -sulfate. 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 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.

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 H2O, thus, indicating their potential use as optimal oil-water separation material.

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, Xray 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 chargedischarge 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).

In this article, Fe-doped carbon aerogels from sodium alginate were used for the removal of methylene blue (MB) in water. Under acidic condition, the sample carbonized at 700 °C (T700) undergoes Fe-C micro-electrolysis to produce highly chemically active Fe2+ and [H] to degrade MB. Under neutral or alkaline conditions, Fe2+ produced by Fe-C micro-electrolysis become Fe(OH)3, which can effectively adsorb MB. In addition, when T700 combines with H2O2 to form Fenton system, the MB removal efficiency was significantly improved. The Fe-doped carbon aerogels can be used in wastewater treatment and when combine the materials with H2O2 can greatly improve the MB removal efficiency.

杂原子掺杂是提升多孔炭材料性能的有效方法之一,其中氮原子掺杂以其原料来源广、制备工艺简单成为了杂原子掺杂的研究热点.本文对近年来氮掺杂多孔炭材料的研究进行了总结,对直接热解法、水热合成法、模板法、化学气相沉积法和后处理法制备氮掺杂多孔炭材料的研究进展进行了综述,同时介绍了氮掺杂多孔炭材料在吸附、催化和电化学领域的应用情况.最后对氮掺杂多孔炭材料今后的研究方向进行了展望.

A mesoporous PR-Fe@MnO2 structure designed for high-performance supercapacitor was successfully prepared. The PR-Fe@MnO2 material, with conductive network structure, was constructed using a high temperature potassium ferrate (K2FeO4) and manganous acetate (Mn(CH3COO)2·4H2O) treatment process. During high-temperature carbonization, a portion of amorphous carbon generated a multi-layer graphene structure, causing PR-Fe@MnO2 to exhibit a high degree of graphitization. After doping, the transition metal Mn was investigated theoretically by performing density functional theory calculations. The results suggesting that doping of moderate Mn ions in the PR-Fe lattice improved the interactions between the OH− ions in the electrolyte and the Mn metal center, which also improved the electrical conductivity of the electrode. The Mn composition also increased the specific area for more electroactive sites and reduced the charge transfer resistance. As a result, PR-Fe@MnO2-1.5 had the highest specific capacitance of 601 F/g at 1.0 A/g and superior cycling stability with 97.8% capacitance retention after 10,000 cycles. Furthermore, the assembled PR-Fe@MnO2-1.5//PR-Fe@MnO2-1.5 symmetric supercapacitor provided a specific energy density of 25.7 Wh/kg at a power density of 384.9 W/kg. Thus, the excellent electrochemical performance of the PR-Fe@MnO2-1.5 composite makes it a promising electrode material for practical applications such as charge storage and in other pseudocapacitors.