We successfully synthesized a porous carbon material with abundant hexagonal boron nitride (h-BN) dispersed on a carbon matrix (p-BN-C) as efficient electrocatalysts for two-electron oxygen reduction reaction ( 2e− ORR) to produce hydrogen peroxide ( H2O2). This catalyst was fabricated via ball-milling-assisted h-BN exfoliation and subsequent growth of carbon structure. In alkaline solutions, the h-BN/carbon heterostructure exhibited superior electrocatalytic activity for H2O2 generation measured by a rotating ring-disk electrode (RRDE), with a remarkable selectivity of up to 90–97% in the potential range of 0.3–0.6 V vs reversible hydrogen electrode (RHE), superior to most of the reported carbon-based electrocatalysts. Density functional theory (DFT) simulations indicated that the B atoms at the h-BN heterostructure interface were crucial active sites. These results underscore the remarkable catalytic activity of heterostructure and provide a novel approach for tailoring carbon-based catalysts, enhancing the selectivity and activity in the production of H2O2 through heterostructure engineering.

Carbon nanomaterials (CNMs) have been the subject of extensive research for their potential applications in various fields, including photovoltaics and medicine. In recent years, researchers have focused their attention on CNMs as their high electrical conductivity, low cost, and large surface area are promising in replacing traditional platinum-based counter electrodes in dye-sensitized solar cells (DSSC). In addition to their electrical properties, CNMs have also displayed antibacterial activity, making them an attractive option for medical applications. The combination of CNMs with metal oxides to form composite materials represents a promising approach with significant potential in various fields, including energy and biology. Here, we introduce porous carbon nanospheres (PCNS) derived from Cocos nucifera L. and its ZnO composite (PCNS/ZnO) as an alternative material, which opens up new research insights for platinum-free counter electrodes. Bifacial DSSCs produced using PCNS-based counter electrodes achieved power conversion efficiencies (PCE) of 3.98% and 2.02% for front and rear illumination, respectively. However, with PCNS/ZnO composite-based counter electrodes, the efficiency of the device increased significantly, producing approximately 5.18% and 4.26% for front and rear illumination, respectively. Moreover, these CNMs have shown potential as antibacterial agents. Compared to PCNS, PCNS/ZnO composites exhibited slightly superior antibacterial activity against tested bacterial strains, including gram-positive Bacillus cereus (B. cereus) and Staphylococcus aureus (S. aureus), and gram-negative Vibrio harveyi (V. harveyi) and Escherichia coli (E. coli) with MIC values of 125, 250, 125, and 62.5 μg/ml, respectively. It is plausible that the outcomes observed were influenced by the synergistic effects of the composite material.

The raw material selected for this research was Brazil chestnut shells (BCs), which were utilized to gain porous carbon as a positive electrode for lithium–sulfur batteries (LSBs). The effects of N/S co-doped on the electrochemical properties of porous carbon materials were studied using thiourea as nitrogen and sulfur sources. The experimental results indicate that the N/S co-doped carbon materials have a higher mesopore ratio than the undoped porous carbon materials. The porous carbon material NSPC-2 has a lotus-like structure with uniform pore distribution. The N and S doping contents are 2.5% and 5.4%. The prepared N/S co-doped porous carbon materials were combined with S, respectively, and three kinds of sulfur carbon composites were obtained. Among them, the composite NSPC-2/S can achieve the initial specific discharge capacity of 1018.6 mAh g− 1 at 0.2 C rate. At 1 C rate, the initial discharge capacity of the material is 730.6 mAh g− 1, and the coulomb efficiency is 98.6% and the capacity retention rate is 71.5% after 400 charge–discharge cycles.

We have intended and preparation of hierarchically absorbent materials were covered with a NiMn2O4 and acts as a catalyst for azo dye degradation. The polyaromatic-based (PA) absorbent compounds were initially constructed by bromomethylated aromatic hydrocarbons which undergo self-polymerization in presence of ZnBr as a reagent and cross linker is bromomethyl methyl ether. The absorbent black materials with a 3D network were prepared by direct carbonization and activation of the as-prepared PA. The hydrothermal method was adapted for the preparation of carbon hybrid material C@NiMn2O4 powder's catalytic activity is effective in reducing p-nitrophenol to p-aminophenol and decolorizing carbon-based dyes like methyl orange (MO), methyl yellow (MY), and Congo red (CR) in aqueous media at 25 °C when NaBH4 is added. UV–visible spectroscopy was used to analyze the dyes' breakdown at regular interval.

This study prepares highly porous carbon (c-fPI) for lithium-ion battery anode that starts from the synthesis of fluorinated polyimide (fPI) via a step polymerization, followed by carbonization. During the carbonization of fPI, the decomposition of fPI releases gases which are particularly from fluorine-containing moiety (–CF3) of fPI, creating well-defined microporous structure with small graphitic regions and a high specific surface area of 934.35 m2 g− 1. In particular, the graphitic region of c-fPI enables lithiation–delithiation processes and the high surface area can accommodate charges at electrolyte/electrode interface during charge–discharge, both of which contribute electrochemical performances. As a result, c-fPI shows high specific capacity of 248 mAh g− 1 at 25 mA g− 1, good rate-retention performance, and considerable cycle stability for at least 300 charge–discharge cycles. The concept of using a polymeric precursor (fPI), capable of forming considerable pores during carbonization is suitable for the use in various applications, particularly in energy storage systems, advancing materials science and energy technologies.

Large-area porous carbon is easily produced for supercapacitors from polyvinylidene chloride (PVDC) and polyvinylidene fluoride (PVDF) precursors, composed of carbon backbone and attached heteroatoms. The released heteroatoms during pyrolysis leave the porous carbon. This study explored the activation of both precursors using chemical agents (ZnO, Mg(OH)2, and KOH) to develop carbon with multiple micropores and mesopores. The activation process and relevant precursors were studied to implement synthesized porous carbon as an electrode in supercapacitors. During the activation of PVDC-resin, ZnO served both as templates and activating agents, while Mg(OH)2 served only as a template, and KOH served as an activating agent. For activation of PVDF, ZnO acted as a template and activating agent, whereas Mg(OH)2 and KOH impeded activation owing to side reactions. Therefore, with the above chemical agents, PVDC-resin was converted to carbon with a higher surface area than PVDF. The porous carbon produced using PVDC-resin with KOH had the highest specific capacitance of 137 F g− 1 and rate performance of 79% at 50 mV s− 1 (vs. 5 mV s− 1) owing to the successful creation of micropores and mesopores. This study identifies optimal conditions for synthesizing porous carbon using polymer precursors and chemical agents for supercapacitors.

Oxygen-rich porous carbon is of great interest for energy storage applications due to its improved local electronic structures compared with unmodified porous carbon. However, a tunable method for the preparation of oxygen-rich porous carbon with a special microstructure is still worth developing. Herein, a novel modification of porous carbon with different microstructures is facilely prepared via low-temperature solvothermal and KOH activation methods that employ the coal tar and eight substances, such as cellulose as carbon source and modifier, respectively. By testing the yield, surface group structure, lattice structures, morphology, thermal weight loss, and specific capacitance of carbonaceous mesophase, cellulose–hydrochloric acid is identified as the additive for the preparation of oxygen-rich coal tar-based porous carbon. The obtained porous carbon displays a specific surface area of up to 859.49 m2 g− 1 and an average pore diameter of 2.39 nm. More importantly, the material delivers a high capacity of 275.95 F g− 1 at 0.3 A g− 1 and maintains a high capacitance of 220 F g− 1 even at 10 A g− 1. When in a neutral electrolyte, it can still retain a reversible capacity of 236.72 F g− 1 at 0.3 A g− 1 and 136.79 F g− 1 at 10 A g− 1. This work may provide insight into the design of carbon anode materials with high specific capacity.

In recent times, there has been a significant demand for supercapacitors in energy storage applications due to their rapid charging– discharging capabilities, high power density, and excellent stability. Nevertheless, the synthesis of electrode materials with a substantial surface area, exceptionally high porosity, and superior electrochemical performance is still challenging. Activated carbons with a distinctive porous structure and exceptional electrochemical properties emerged as promising electrode materials for supercapacitors. In this study, we used a porous activated carbon (PAC) derived from petroleum coke followed by KOH activation as an efficient anodic electrode material. The ultra-high Brunauer–Emmett–Teller surface area of 2105.6 m2 g− 1 with stacked layers of carbon atoms arranged in a two-dimensional hexagonal structure makes the PAC an efficient candidate for a supercapacitor electrode. The PAC delivers a specific capacitance of 470 F g− 1 at a current density of 0.5 A g− 1 over a potential window of 0 to −1 V. The excellent cycling stability in a three-electrode setup with a capacitance retention of ⁓98% even at a high current density of 10 A g− 1 makes the PAC a potential anodic electrode material for high-performance supercapacitor applications.

본 연구에서는 분리막 생물반응기(membrane bioreactor, MBR)에서 발생되는 생물막오염 완화에 탁월한 효과를 가진 분리막을 개발할 목적으로, 친수성 산소 기능기가 많은 탄소나노구체(carbon nanosphere, CNS)를 합성한 뒤, 이를 첨가 제로 활용하여 친수성과 다공성 기공 구조를 갖는 고성능 한외여과막을 제조하였다. CNS는 막 표면에 초승달 모양의 기공을 형성하였고, CNS 함량을 4.6 wt%까지 증가시킴에 따라 최대기공 크기보다 큰 결함을 야기하지 않으면서 평균 표면 기공 크 기를 약 40% 증가시키는 것으로 나타났다. 또한, CNS 복합막의 다공성 기공 구조는 CNS의 등방성 형태와 상대적으로 낮은 입자 수밀도 덕분에 CNS 첨가에 따른 고분자 용액의 점도 급등이 방지됐기 때문이라고 판단된다. 그러나 너무 다공성이 커 지게 되면 기계적 물성이 저하되므로, 기공구조와 기계적 성질을 포함한 종합적인 고려를 했을 때 CNS2.3이 가장 우수하다 고 관측되었다. CNS2.3은 CNS0에 비해 수투과도가 2배 이상 높을 뿐만 아니라, MBR 공정에서 분리막 세정이 요구될 때까 지의 운전 시간도 5배 이상 연장시킨 것으로 확인되었다.

The complexation of silicon with carbon materials is considered an effective method for using silicon as an anode material for lithium-ion batteries. In the present study, carbon frameworks with a 3D porous structure were fabricated using metal–organic frameworks (MOFs), which have been drawing significant attention as a promising material in a wide range of applications. Subsequently, the fabricated carbon frameworks were subjected to CVD to obtain silicon-carbon complexes. These siliconcarbon complexes with a 3D porous structure exhibited excellent rate capability because they provided sufficient paths for Li-ion diffusion while facilitating contact with the electrolyte. In addition, unoccupied space within the silicon complex, combined with the stable structure of the carbon framework, allowed the volume expansion of silicon and the resultant stress to be more effectively accommodated, thereby reducing electrode expansion. The major findings of the present study demonstrate the applicability of MOF-based carbon frameworks as a material for silicon complex anodes.

A carbon matrix for high-capacity Li/Na/K-alloy-based anode materials is required because it can effectively accommodate the variation in the volume of Li/Na/K-alloy-based anode materials during cycling. Herein, a nanostructured porous polyhedral carbon (PPC) was synthesized via a simple two-step method consisting of carbonization and selective acid etching, and their electrochemical Li/Na/K-ion storage performance was investigated. The highly uniform PPC, with an average particle size of 800 nm, possesses a porous structure and large specific surface area of 258.82 cm2 g– 1. As anodes for Li/Na/K-ion batteries (LIBs/NIBs/KIBs), the PPC matrix exhibited large initial reversible capacity, fast rate capability (LIB: ~ 320 mAh g– 1 at 3C; NIB: ~ 140 mAh g– 1 at 2C; KIB: ~ 110 mAh g– 1 at 2C), better cyclic performance (LIB: ~ 550 mAh g– 1; NIB: ~ 210 mAh g– 1; KIB: ~ 190 mAh g– 1 at 0.2C over 100 cycles), high ionic diffusivity, and excellent structural robustness upon cycling, which demonstrates that the PPC matrix can be highly used as a carbon matrix for high-capacity alloy-based anode materials for LIBs/NIBs/KIBs.

In this work, norepinephrine (NE) was determined by an electrochemical sensor represented by a carbon paste electrode boosted using nitrogen-doped porous carbon (NDPC) derived from Spirulina Platensis microalga anchored CoFe2O4@ NiO and 1-Ethyl-3-methylimidazolium acetate (EMIM Ac) ionic liquid. The morphological characteristics of the catalyst were recorded by field emission scanning electron microscope (FE-SEM) images. Moreover, the electrochemical behavior of norepinephrine on the fabricated electrode was checked using various voltammetric methods. All tests were done at pH 7.0 as the optimized condition in phosphate buffer solution. The results from linear sweep voltammetry revealed that the electro-oxidation of norepinephrine was diffusion, and the diffusion coefficient value was obtained by chronoamperometry (D⁓6.195 × 10– 4). The linear concentration of the modified electrode was obtained from 10 to 500 μM with a limit of detection of 2.26 μM using the square wave voltammetry (SWV) method. The sensor selectivity was investigated using various species, and the results from stability and reproducibility tests showed acceptable values. The sensor's efficiency was tested in urine and pharmaceutical as real samples with recovery percentages between 97.1% and 102.82%.

In recent years, supercapacitors have attracted extensive attention due to their advantages such as fast charge and discharge rate, high power density and long cycle life. Because of its unique porous structure and excellent electrochemical properties, heteroatom-doped porous carbon (HPC) is deemed as a promising electrode material for supercapacitors. However, it is a great challenge to synthesize electrode materials with large surface area, ultra-high porosity and good electrochemical performance. In this work, two-dimensional conjugated microporous polymers (CMPs) containing ketones were synthesized by a simple one-step coupling reaction and used as carbon precursors. A series of samples (CMP-Ts) were prepared with the procedures of coupling reaction and carbonization. The optimized carbon material has high specific surface area (up to 2229.85 m2 g− 1), porous structure, high specific capacitance (375 F g− 1 at 0.5 A g− 1), and good cycling stability (capacitance retention of 98.8% after 1000 cycles at 5 A g− 1). Further, the supercapacitor has an energy density of 28.8 Wh kg− 1 at a power density of 5000 W kg− 1. This work lays a foundation for the preparation of carbon materials using microporous polymer as a precursor system, provides a new way of thinking, and demonstrates a great potential of high-performance supercapacitors.

Refined structured tin dioxide gets the amount of attraction because of its low cost and stability. The C@SnO2 nanospheres with mesoporous structures were produced using the hard template method in this work. The C@SnO2 is primarily gained attributed to the dehydration condensation of C6H12O6 and the hydrolysis of SnCl4 ·5H2O. The morphology of the C@SnO2 was analyzed by physical characterization and the diameter of the obtained C@SnO2 was around 138 nm. When C@SnO2 was applied to lithium-ion batteries as anode material, it performed outstanding electrochemical properties, with a capacity of 735 and 539 mA h g− 1 maintained at 1000 and 2000 mA g− 1, respectively. Furthermore, it exhibits favorable discharge/ charge cycle stability. This is probably because of the more chemically redox active sites provided by C@SnO2 nanocomposites and it also allows fast ion diffusion and electron migration.

The development of functional carbon materials using waste biomass as raw materials is one of the research hotspots of lithium-sulfur batteries in recent years. In this work, used a natural high-quality carbon source—coffee grounds, which contain more than 58% carbon and less than 1% ash. Honeycomb-like S and N dual-doped graded porous carbon (SNHPC) was successfully prepared by hydrothermal carbonization and chemical activation, and the amount of thiourea used in the activation process was investigated. The prepared SNHPC showed excellent electrochemical energy storage characteristics. For example, SNHPC-2 has a large pore volume (1.85 cm3·g− 1), a high mesoporous ratio (36.76%), and a synergistic effect (S, N interaction). As the cathode material of lithium-sulfur batteries, SNHPC-2/S (sulfur content is 71.61%) has the highest specific capacity. Its initial discharge-specific capacity at 0.2 C is 1106.7 mAh·g−1, and its discharge-specific capacity after 200 cycles is still as high as 636.5 mAh·g−1.

In this study, waste corrugated paper was used as carbon precursor with KOH-NaOH mixture (mole ratio was 51:49 and the melting point is 170 °C) as activator to prepare porous carbon at different reaction temperature and different mass ratio of KOH-NaOH mixture/waste corrugate paper fiber. The micro-morphology, pore structure information and composition of porous carbon were analyzed, and the formation mechanism of pores was investigated. The effect of activator amount and pyrolysis temperature on the morphology and structure of porous carbon were studied. The adsorption capacity of porous carbon was evaluated with the methylene blue as model pollutant. The effect of adsorbent amount, adsorption time and temperature on the adsorption performance of the porous carbon were analyzed. The maximum specific surface area is 1493.30 m2 ·g−1 and the maximum adsorption capacity of methylene blue is 518 mg·g−1. This study provides a new idea for efficient conversion and utilization of waste paper.

In this work, subabul wood biomass was used to prepare carbon adsorbents by physical and chemical activation methods at various carbonization temperatures. The properties of the carbon adsorbents were estimated through characterization techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, X–ray photo electron spectroscopy, laser Raman spectroscopy, scanning electron microscopy, CHNS-elemental analysis and N2 adsorption studies. Subabul-derived carbon adsorbents were used for CO2 capture in the temperature range of 25–70 °C. A detailed adsorption kinetic study was also carried out. The characterization results indicated that these carbons contain high surface area with microporosity. Surface properties were depended on treatment method and carbonization temperature. Among the carbons, the carbon prepared after treatment of H3PO4 and carbonization at 800 °C exhibited high adsorption capacity of 4.52 m.mol/g at 25 °C. The reason for high adsorption capacity of the adsorbents was explained based on their physicochemical characteristics. The adsorbents showed easy desorption and recyclability up to ten cycle with consistent activity.

Biomass-derived porous carbon is an excellent scientific and technologically interesting material for supercapacitor applications. In this study, we developed biomass-derived nitrogen-doped porous carbon nanosheets (BDPCNS) from cedar cone biomass using a simple KOH activation and pyrolysis method. The BDPCNS was effectively modified at different temperatures of 600 °C, 700 °C, and 800 ℃ under similar conditions. The as-prepared BDPCNS-700 electrode exhibited a high BET surface area of 2883 m2 g− 1 and a total pore volume of 1.26 cm3 g− 1. Additionally, BDPCNS-700 had the highest electrical conductivity (11.03 cm− 1) and highest N-doped content among the different electrode materials. The BDPCNS-700 electrode attained a specific capacitance of 290 F g− 1 at a current density of 1 A g− 1 in a 3 M KOH electrolyte and an excellent longterm electrochemical cycling stability of 93.4% over 1000 cycles. Moreover, the BDPCNS-700 electrode had an excellent energy density (40.27 Wh kg− 1) vs power density (208.19 W kg− 1). These findings indicate that BDPCNS with large surface areas are promising electrode materials for supercapacitors and energy storage systems.