Porous Carbon Samples Research Articles

Carbon-Supported Fe-Based Catalyst for Thermal-Catalytic CO2 Hydrogenation into C2+ Alcohols: The Effect of Carbon Support Porosity on Catalytic Performance

Carbon materials supported Fe-based catalysts possess great potential for the thermal-catalytic hydrogenation of CO2 into valuable chemicals, such as alkenes and oxygenates, due to the excellent active sites’ accessibility, appropriate interaction between the active site and carbon support, as well as the excellent capacities in C-O bond activation and C-C bond coupling. Even though tremendous progress has been made to boost the CO2 hydrogenation performance of carbon-supported Fe-based catalysts, e.g., additives modification, the choice of different carbon materials (graphene or carbon nanotubes), electronic property tailoring, etc., the effect of carbon support porosity on the evolution of Fe-based active sites and the corresponding catalytic performance has been rarely investigated. Herein, a series of porous carbon samples with different porosities are obtained by the K2CO3 activation of petroleum pitch under different temperatures. Fe-based active sites and the alkali promoter Na are anchored on the porous carbon to study the effect of carbon support porosity on the physicochemical properties of Fe-based active sites and CO2 hydrogenation performance. Multiple characterizations clarify that the bigger meso/macro-pores in the carbon support are beneficial for the formation of the Fe5C2 crystal phase for C-C bond coupling, therefore boosting the synthesis of C2+ chemicals, especially C2+ alcohols (C2+OH), while the limited micro-pores are unfavorable for C2+ chemicals synthesis owing to the sluggish crystal phase evolution and reactants’ inaccessibility. We wish our work could enrich the horizon for the rational design of highly efficient carbon-supported Fe-based catalysts.

Size Confinement Strategy Effect Enables Advanced Aqueous Zinc–Iodine Batteries

AbstractAqueous Zn–I2 batteries have considerable potential owing to their environmental friendliness and high safety. However, the slow iodine conversion kinetics and shuttle effect prevent their practical applicability. In this study, a series of Zn‐MOF‐74 rods with controllable diameters of 40–500 nm are facilely prepared, denoted as P1–P5. A size confinement strategy effect of Zn‐MOF‐74 derived porous carbon as iodine hosts is proposed to suppress the formation of undesirable iodine species, such as I3− and I5−. Moreover, the graphitization degree of porous carbon samples, including P2‐900, P2‐1000, and P2‐1100, play a critical effect on the iodine conversion kinetics. The P2‐1000 sample possesses a high conductive skeleton and abundant mesopores, which improve the adsorption ability toward iodine species. The electrochemical tests and the in situ technology reveal the size confinement strategy effect and the conversion mechanism of iodine. As a result, the I2@P2‐1000 cathode exhibits a superior discharge capacity of 179.9 mA h g−1 at 100 mA g−1 and exceptional long‐term cycle ability after 5000 cycles. Furthermore, the soft batteries and the flexible quasi‐solid‐state batteries are capable of powering devices, promising to exhibit tremendous adaptability and realize flexible electronic devices in various scenarios.

Pore properties and CO2 adsorption performance of activated carbon prepared from various carbonaceous materials

In this study we prepared porous carbon samples from various carbonaceous materials, such as biomass and coal, and evaluated their CO2 adsorption performance. We first prepared activated carbon samples by heat treatment of the carbonaceous materials with a mixture of melamine as a nitrogen source and K2CO3 as a chemical activator. We then investigated their pore properties in detail and tested the CO2 adsorption performance of the prepared activated carbon samples. We found that activated carbon with well-developed pores could be prepared using materials with low carbon and ash content. Significant correlation was found among the specific surface area (SSA: 1840–2640 m2/g), micropore (0.85–1.46 cm3/g) volume, and CO2 adsorption of the prepared activated carbon samples, indicating that the SSA and micropore volume affected the CO2 adsorption performance (400–530 mg/g). Based on these results, we devised guidelines for producing activated carbon with high CO2 adsorption performance.

Inspired by the Seeking Knowledge Strategy for Analects of Confucius to Screen Highly Electrochemically Active Porous Carbon: The Critical Source of Electroactive Sites

In this work, the forestry wastes are converted into a series of porous carbons using H3PO4 activation. These porous carbons feature a large specific surface area (1045.20 m2 g−1) and porosity that combines micro‐, meso‐, and macropores in various amounts depending on the fuel properties recorded for precursors used. Importantly, the C content recorded for forestry waste is one of the crucial factors in defining the specific surface area of the derived porous carbons. In addition, the total capacitance of the pine‐sawdust‐based porous carbon (PS‐C) sample is the highest, such as 220.55 F g−1 upon 5 mV s−1. Notably, the electrical double‐layer capacitance recorded for the samples remains essentially constant with increasing scan rates, such as ≈91.50 F g−1 for the olive‐shell‐based porous carbon, ≈123.70 F g−1 for PS‐C, and ≈105.66 F g−1 for the pine‐needle‐based porous carbon. Encouragingly, the pore‐associated sp3 site holds significant roles in the electrochemical application of the porous carbons. More importantly, the O/C value recorded for the precursor can be employed as a universal predictor of electrochemically active sites produced in porous carbons. In the findings, crucial insights are exhibited into the optimized fabrication of porous carbon with target electrochemically active sites for other applications such as catalysis.

Enhanced removal of Pb2+, Cd2+ and Zn2+ ions on porous carbon from aqueous solutions by capacitive deionization: Performance study and underlying mechanism

In this paper, nitrogen-doped porous carbon materials were successfully prepared using sucrose and activated carbon as raw materials and NH4Cl as nitrogen dopant by foaming and pyrolysis. The nitrogen-doped porous carbon (NPC-1) sample has a large specific surface area (798.425 m2/g) and good electrochemical properties. Capacitive deionization (CDI) tests showed that the removal rate was over 87% and 85% in the mixture of three ions (Pb2+, Cd2+ and Zn2+), when the initial concentration of ternary mixed solution was 10 mg/L and 20 mg/L and the voltage was 1.2 V. Density-functional-transfer theory (DFT) calculations revealed that materials containing pyridine-N and pyrrolic-N have better adsorption properties for Pb2+, Cd2+ and Zn2+ than materials containing graphite-N and materials without doped nitrogen. Meanwhile, the adsorption energy of pyridine-N and pyrrolic-N models for Pb atom are larger than those of pyridine-N and pyrrolic-N models for Cd and Zn atoms. This indicated that the NPC-1 electrode has better electrosorption capacity for Pb2+, which was consistent with the experimental results. After twenty cycles experiments, the NPC-1 electrode maintained a high removal rate for Pb2+ (95%), Cd2+ (82%), and Zn2+ (87%). This showed that the electrode material has a good recycling regeneration ability.

Electrochemical properties of porous carbon derived from coal gasification fine ash via low-temperature alkaline fusion and KOH activation

Coal gasification fine ash (a carbon-based solid waste, CGFA) is regarded as the ideal precursors for constructing carbon-based porous materials due to their low cost, high yield, high carbon content, and abundant pore structure. This study employed CGFA as the raw material and prepared porous carbon samples with a high specific surface area (SBET) of 2167.5 m2/g and a high mesoporous ratio of 80.1 % (by volume) using an low-temperature alkaline fusion-KOH activation method. The sample exhibited ideal double-layer capacitance behavior with a mass-specific capacitance of 219.7 F/g (at 1 A/g) and a capacitance retention rate of 82.6 % (at 1 A/g–20 A/g). The energy density of the assembled symmetrical supercapacitor was 13.4 Wh/kg (corresponding to a power density of 475 W/kg), and the capacitance retention rate was 97.9 % after 15,000 cycles. In summary, this work prepared high-performance porous carbon for supercapacitors from widely existing industrial waste CGFA, which provides a feasible strategy for the application of CGFA derived porous carbon in energy storage materials.

Nitrogen-doped porous carbon transformed from polymer carbon nitride for persulfate activation towards efficient degradation of tetracycline via the electron transfer-dominated non-radical pathway

BackgroundMetal-free carbon materials have been extensively researched for the removal of aqueous pollutants by persulfate activation. However, it was still worth exploring the contribution of adsorption of carbon materials to the catalytic efficiency as well as the ROS degradation pathway. MethodsA series of g-C3N4 and nitrogen-doped porous carbon materials were prepared by combining l-ascorbic acid with melamine-cyanuric acid (MCA) for the removal of tetracycline from wastewater. The carbon materials were analyzed by using XRD, XPS, Raman and other characterization methods. Furthermore, the effect of different reaction parameters on TC degradation was investigated, and the active species were identified by scavenging experiments and EPR. Significant findingsThe prepared porous carbon sample LAA-NC0.6 has a high nitrogen content of 31.93 at%. LAA-NC0.6 could completely remove TC within 40 min with first-order kinetic constant as high as 0.14995 min−1, which was 167-fold higher than that of pristine g-C3N4. Catalytic studies showed that the degradation of TC was a non-radical pathway dominated by electron transfer and that adsorption had a marked influence on the catalytic performance of the LAA-NC0.6/PS system.

Effective solar-driven interfacial water evaporation-assisted adsorption of organic pollutants by a activated porous carbon material

Recently, solar-driven interfacial water evaporation (SDIWE) has attracted worldwide attention owing to its potential use in seawater desalination and wastewater purification. Nevertheless, how to effectively use the inevitable conduction heat loss and eliminate organic pollutants are still challenging. We report the SDIWE- assisted adsorption of organic pollutants by using the conduction heat loss to improve the total energy efficiency of the SDIWE system. Porous carbon (PC) and activated PC were prepared by a simple recrystallizing salt template-assisted carbonization and KOH activation method. After activation, the activated PC sample with a PC : KOH mass ratio of 1 : 4 (PC-A4) has a hierarchical porous structure, a better absorption capacity in the spectral region of 200-2500 nm, a high specific surface area of 1 867.71 m2 g−1 and a large pore volume of 1.04 cm3 g−1. Based on this, PC-A4 has a high evaporation rate and energy efficiency, which can be further increased by regulating the mass of the water body. Subsequently, the conduction heat generated by the SDIWE system was used for SDIWE-assisted adsorption. Notably, the maximum amount of rhodamine B adsorbed by PC-A4 is 1 610 mg g−1 at a conduction temperature of 309 K, which is higher than that of the same sample at 298 K. Consequently, this work offers a promising approach for effectively using the conduction heat loss of the SDIWE system and developing it for water purification.

Self-assembled nano Co-Ni pompon structured hierarchical porous carbon and the excellent electrochemical capacity

Supercapacitor is an energy storage device with excellent performance which has been studied in recent years. Biomass-based porous carbon materials are widely used as electrode materials for supercapacitors because of their good pore structure and electrical conductivity. A unique nanoscale pompon with structured porous carbon as core was synthesized by a two-stage activation of H3PO4-K2C2O4 combined with hydrothermal self-assembly in this research. Results showed that the specific surface area of the hierarchical porous carbon sample was up to 1608.1 m2/g with the mesoporous ratio of 54.26%. The self-doped Co-Ni elements were successfully entered into the channel of carbon core and then the self-assembled nano pompon epidermis was formed. Interleaving nanorods with unique characteristics as dispersion at the bottom and aggregation at the top were evenly grown on the surface of the pompon, forming a 3D network structure with a mass of cavities, which brought with excellent faradaic pseudocapacitance of electrode materials. The energy density and power density of the asymmetric supercapacitor assembled by nano pompom and porous carbon reach 30.4 Wh/kg and 1367.1 W/kg respectively.

Synergistic effect of nitrogen and oxygen dopants in 3D hierarchical porous carbon cathodes for ultra-fast zinc ion hybrid supercapacitors

Zinc-ion hybrid supercapacitor is one of the most promising electrochemical energy storage devices for the applications needing both high energy densities and power densities. Nitrogen doping is an effective way to enhance the capacitive performance of porous carbon cathodes in zinc-ion hybrid supercapacitor. However, accurate evidence is yet needed to demonstrate how nitrogen dopants influence the charge storage of Zn2+ and H+ cations. Herein, we prepared 3D interconnected hierarchical porous carbon nanosheets by a one-step explosion method. The effect of nitrogen dopants on pseudocapacitance was analyzed by the electrochemical behaviors of as-prepared porous carbon samples with similar morphology and pore structure but different nitrogen and oxygen doping levels. Ex–situ XPS and DFT calculation demonstrate that nitrogen dopants promote the pseudocapacitive reactions by lowering the energy barrier for the change of oxidation states of carbonyl moieties. Owing to the improved pseudocapacitance by nitrogen/oxygen dopants and fast diffusion of Zn2+ ions in 3D interconnected hierarchical porous carbon matrix, the as-constructed ZIHCs show both high gravimetric capacitance (301 F g−1 at 0.1 A g−1) and excellent rate capability (a capacitance retention of 30% at 200 A g−1).

Effective conversion of waste banana bract into porous carbon electrode for supercapacitor energy storage applications

Herein, high capacitive supercapacitor performance of porous carbon electrode material obtained from waste banana bract was created by two-step chemical activation using KOH. Based on the findings of the structural analysis, the effective pore size contribution to the electrochemical performance in a neutral electrolyte (1M Na2SO4) was examined using cyclic voltammetry, galvanostatic and electrochemical impedance spectroscopy techniques on porous carbon samples activated at temperatures between 500 and 800°C and exhibiting Brunauer–Emmett–Teller surface areas ranging from 22.9 to 513 m2g−1. The highest specific capacitance of 472 Fg−1 was obtained by the typical rectangular CV profile in the potential window range of -0.2 to +1 V for 800 °C. At 1 Ag−1, the high energy density of 86 Whkg−1 at 1.28 kWkg−1 of power density was reached with the capacitance retention of 93.5% at 5000 cycles at 10 Ag−1. These findings demonstrate the viability of using porous carbon from waste bracts in high-performance supercapacitors.

Microalgae Derived Nano Carbon-Sulfur Composite Cathodes for Sulfur Batteries

Nano porous carbon and sulfur composites were prepared using microalgae as carbon precorsors by the melt diffusion method. Initially, nano porous carbon materials were synthesized by the hydrothermal method, followed by the chemical activation method with and without ferrocene as catalyst. Therefore, we have two types of porous carbon samples, the first sample was denoted as NPC (preparation with ferrocene) and the other one is PC (preparation without ferrocene) Brunauer–Emmett–Teller analysis indicated that the surface area and total pore volume (at P/P o) of NPC samples were lower than those of the PC samples. The NPC and PC samples were then mixed with sulfur to obtain NPC-S and PC-S composites. Those composites were then utilized as cathode materials for Lithium Sulfur Battery. The NPC-S samples with a sulfur content of 76.7 wt.% exhibited a higher initial specific capacity and better cycle retention than those of the PC-S. Optimized sulfur content for NPC-S was investigated to handle the shuttle effect problem. improved electrochemical performance is attributed to the increased conductivity of the NPC-S samples and optimized sulfur loading content, which effectively confined lithium polysulfide intermediates.

Preparation of hierarchical porous carbon by pyrolyzing sargassum under microwave: The internal connection between structure−oriented regulation and performance optimization of supercapacitors

To find an effective correlation between the preparation process and the application performance of symmetric supercapacitors, the relationship between the structural characteristics of biomass porous carbon and the electrochemical performances of supercapacitors was studied. Based on a response surface experimental design, the pore structure of biochar produced by the microwave pyrolysis of sargassum was adjusted through the collaborative optimization of key parameters, and graded sargassum porous carbon (SPC) with different pore characteristics was successfully prepared. Three representative samples, SPC−1, SPC−2, and SPC−3, were selected by systematically exploring the effects of the specific surface area (SSA), pore volume (Vtotal), and pore size distribution on the electrochemical performances. The SSA and Vtotal values of SPC−1 were 1500.50 m2 g−1 and 1.0513 cm3 g−1, respectively. The large number of micropores provided space for electronic storage, allowing it to have an excellent electronic storage capacity. The SSA of SPC−2 was 2019.90 m2 g−1, and Vtotal was 1.2241 cm3 g−1. The rich micropores resulted in a good charge–discharge rate. The SSA of SPC−3 was as high as 2103.20 m2 g−1, and Vtotal was 1.4756 cm3 g−1. The micron−level mesopores between the SPC−3 carbon skeletons acted as ion buffer reservoirs to shorten the ion diffusion distance and produce excellent rate performances. Subsequently, the morphology and surface properties of porous carbon samples were characterized. The study revealed that hierarchical porous carbon materials with excellent properties must achieve a balance of the microstructure and surface properties and their influence on the electrochemistry. A higher degree of graphitization could bring about a high pore regularity, thereby optimizing the ion transport kinetics. Heteroatoms could increase redox active surface sites and provide additional pseudocapacitance, but the resulting defect structure formed a large number of pores with high edge roughness in the carbon material, which had a certain negative impact on the capacity properties of the materials. The above findings can provide technical support and a theoretical basis for controlling the pore networks and directionally optimizing the performances of supercapacitors by adjusting the pore structure of biochar.

Effect of chemical activators on polyphosphazene-based hierarchical porous carbons and their good CO2 capture

In this paper, various hierarchically porous carbons have been prepared from polyphosphazene microspheres by using different activating agents (K2CO3, KOH, or NaOH) and the effects of chemical activators on morphology, pore structure, element component and CO2 uptakes of porous carbons were investigated. With different activators, the resultant porous carbons exhibit different morphology, specific surface area, and pore size distribution (PSD). Among them, the typical sample HPCs - K2CO3 has the largest values of SBET (1681 m2 g−1), Smicro (996 m2 g−1), and Vmicro (0.46 cm3 g−1). Then, using them as sorbents for CO2 capture, their CO2 uptake capability, isosteric heat (Qst), selectivity, and reversibility were investigated and compared. Among them, HPCs - K2CO3 shows the highest uptakes of 6.4 mmol g−1 (282 mg g−1) at 273 K/1 bar and 4.3 mmol g−1 (188 mg g−1) at 298 K/1 bar. Based on the linear fitting method, this high CO2 uptake could be mainly attributed to the large micropore volume of sorbents, and also has the contribution of multiple heteroatoms in the porous carbon matrix. Furthermore, all the prepared porous carbon samples exhibit low isosteric heat (Qst) (21.24–22.13 kJ mol−1) with high CO2 uptake (4.53–6.41 mmol g−1 at 273 K), high selectivity of CO2/N2 (IAST selectivity of HPCs – K2CO3: 450 at 273 K, 160 at 298 K), and good recyclability, and the regeneration of them is easy to achieve.

Activated carbons prepared from hazelnut shell waste by phosphoric acid activation for supercapacitor electrode applications and comprehensive electrochemical analysis

In this study, the activated carbon was produced from hazelnut-shell wastes using a single-step chemical activation. The activated carbon with a specific surface area of 1363 m2 g−1 and micropore volume of 0.52 cm3 g−1 was used to synthesize magnetic activated carbon to investigate the influence of the magnetization on the capacitive performance. The porous carbon samples were characterized using various techniques and analyses including N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, Raman, and vibrating sample magnetometer. The prepared electrodes were evaluated by cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. The specific capacitance values of the activated carbon electrode and magnetic-activated carbon electrode were 247.8 F g−1 and 76.23 F g−1 at 0.75 A g−1, respectively. Moreover, the impedance responses were mathematically modeled using an equivalent electric circuit. Although a more homogeneous current distribution was obtained for the magnetic activated carbon, the higher constant phase element coefficient of the activated carbon demonstrated a higher capability of adsorption of mobile ions. The results showed the higher capacitive performance of the activated carbon electrodes for energy applications.

Nitrogen-doped hierarchically porous carbon obtained via single step method for high performance supercapacitors

In the present work, nitrogen doped hierarchically activated porous carbon (APC) samples have been synthesized via single step scalable method using ethylene di-amine tetra acetic acid (EDTA) as precursor and KOH as activating agent. Activated porous carbons with different pore sizes have been developed by varying the activation temperature. SEM, TEM and SAXS analysis suggest that with variation of activation temperature, a hierarchical porous structure with interconnected meso-pore and micro pores has been achieved. The sufficiently high surface area of the synthesized materials provides active sites to enhance the diffusion of ions between the electrolyte and the carbon electrodes. The electrode prepared at 800 °C activated sample exhibited highest specific capacitance of 274 Fg-1 in two electrode setup, at a current density of 0.1 Ag-1 in 1 M aqueous H2SO4. Along with this, it showed maximum energy density of 9.5 Whkg−1 at a power density of 64.5 Wkg-1. The remarkable electrochemical performance reveals that the synthesized nitrogen doped activated carbon electrodes derived from EDTA can be tuned to have optimum pore structure and pore size distribution for better electrochemical performance, so it can be considered as a potential electrode material for applications in electrochemical energy storage.

Bio-based Carbon Electrochemically Decorated with Cu Nanoparticles: Green Synthesis and Electrochemical Performance

This study aimed to synthesize a composite material composed of bio-based, porous carbon matrix and Cu nanoparticles through a simple, low-cost, and environmentally friendly method. Concentrated Kraft black liquor was used as a carbon precursor, and Cu nanoparticles were homogeneously deposited on the carbon matrix using electrochemical deposition. The textural properties determined using N2 isotherms indicated increased surface area of a carbon matrix with a micro-mesoporous structure. Voltammetric tests demonstrated that the composite exhibited catalytic properties for electrochemical CO2 reduction. Compared to the bio-based, porous carbon sample (C matrix), the bio-based carbon electrode electrochemically decorated with Cu nanoparticles (C–Cu composite) exhibited increased current values of approximately 2.4 times, a potential shift of approximately 90 mV, and an onset potential of −1.02 V, under CO2 saturation.

Glucosamine derived hydrothermal carbon electrodes for aqueous electrolyte energy storage systems.

Nitrogen-doped porous hard carbons are synthesized by hydrothermal carbonization method (HTC) using glucosamine as biosource and treated at different carbonization temperatures in nitrogen environment (500, 750, 1000 °C). The electrochemical performances of hard carbons electrode materials for aqueous electrolyte sodium ion batteries are examined to observe the effect of two different voltage ranges (-0.8-0.0) V and (0.0-0.8) V in 1.0 M Na2SO4 aqueous electrolyte. The best electrochemical performances are acquired for the 1000 °C treated glucosamine (GA-1000) porous carbon sample that provides ~96 F/g capacitance value in the negative voltage range (between -0.8 and 0.0) V. The sodium diffusion coefficient of the GA-1000 carbon calculated by electrochemical impedance measurements is found to be 1.5 × 10-14 cm2/s.

Re-utilization of Chinese medicinal herbal residue: waste wormwood rod-derived porous carbon as a low-cost adsorbent for methyl orange removal.

A cost-effective approach was applied to prepare porous carbon samples by the simple carbonization of wormwood rod followed by salt activator (NaCl) activation. The effect of preparation parameters on the characteristics of the wormwood rod-based porous carbons (WWRs) were studied. The properties of these samples were investigated by SEM, BET surface area, X-ray diffraction, FT-IR spectra and X-ray photoelectron spectrometer. The prepared WWRs were applied as new adsorbent materials to remove methyl orange (MO). The experimental results indicated that WWR-800 activated at 800 °C possesses the best adsorption performance. Several factors that affected the adsorption property of the system such as the solution pH, dosing of adsorbent, initial dye concentration and ionic strength were examined. In addition, the thermodynamic parameters and kinetic parameters of MO with WWR-800 were studied. The results indicated that the adsorption of MO on WWR-800 was an endothermic process and non-spontaneous under standard conditions. The maximum equilibrium adsorption capacity of MO on WWR-800 was 454.55 mg/g. After five adsorption/desorption cycles, the adsorption capacity of MO on WWR-800 remained at 94%, which indicated that wormwood rod-based porous carbon possessed good reusability.

Ultra-high specific surface area porous carbon derived from chestnut for high-performance supercapacitor

The preparation of biomass-derived porous carbon having a high specific surface area for high-performance supercapacitors has been recognised as an important research topic in the past decade. In this study, chestnut-pulp-derived porous carbon is prepared by employing a two-step process involving carbonisation and KOH chemical activation for the first time. The synthesized hierarchical porous carbon samples have an ultra-high specific surface area of 2646 m2 g−1 and good conductivity, and their O-doping can be controlled. They exhibit excellent electrochemical performance as carbon electrodes owing to the synergistic effects of their advantageous features. In a three-electrode system, the as-obtained electrode yields a high specific capacitance of 373 F g−1 at 0.5 A g−1 in 6 M KOH electrolyte. Furthermore, it exhibits excellent rate performance with ~70.8% capacity retention when the discharge current increases from 1 to 10 A g−1 and prominent cycling stability with ~99.7% capacity retention after 10000 cycles. These values indicate that chestnut-pulp-based carbon materials have excellent electrochemical properties when used as supercapacitor electrodes and may promote the large-scale application of 3D porous carbons in energy storage.