Carbon Gel Research Articles

A new strategy for semi quantitative analysis of pore structure for lithium-ion battery electrodes

The Lithium ions diffusion dynamic, electrons transfer and the growth of the solid electrolyte interfaces are in close relation to the pore structure of the anodes. The widely used mercury intrusion porosimetry suffers from serious severe reaction with the copper and aluminum substrate, and unable to provide the pore structure evolution in the cross-section direction of the electrode. And the X-ray computed tomography faces limitations in identifying the carbon gel phase and is associated with high costs. Therefore, it is of substantial interest to directly investigate the cross-sectional pore structure from SEM morphologies. In this study, the using of resin protected polishing method to expose the cross-sectional structure is proposed to analyze the porosity evolution of the cross-sectional structure for lithium-ion battery anode. This method can clearly expose the cross-sectional structure of the electrode preventing the disturbance of the height fluctuation of the active particles. The influence of the coating processes on the pore structure is studied with the help of image J software and the machine leaning plug-in. The porosity changes of the electrode along with the coating depth are clearly elucidated. This method provides a convenient and efficient solution on the structure characterization of the electrode in Lithium-ion batteries.

Study of the Factors Influencing the Adsorption of Heavy Metal Pollutants in Water by Activated Carbon Gel Particles

Study of the Factors Influencing the Adsorption of Heavy Metal Pollutants in Water by Activated Carbon Gel Particles

Investigation of Carbonation Kinetics in Carbonated Cementitious Materials by Reactive Molecular Dynamics Simulations.

Calcium carbonate (CaCO3) precipitation plays a significant role during the carbon capture process; however, the mechanism is still only partially understood. Understanding the atomic-level carbonation mechanism of cementitious materials can promote the mineralization capture, immobilization, and utilization of carbon dioxide, as well as the improvement of carbonated cementitious materials' performance. Therefore, based on molecular dynamics simulations, this paper investigates the effect of Si/Al concentrations in cementitious materials on carbonation kinetics. We first verify the force field used in this paper. Then, we analyze the network connectivity evolution, the number and size of the carbonate cluster during gelation, the polymerization rate, and the activation energy. Finally, in order to reveal the reasons that caused the evolution of polymerization rate and activation energy, we analyze the local stress and charge of atoms. Results show that the Ca-Oc bond number and carbonate cluster size increase with the decrease of the Si/Al concentration and the increase of temperature, leading to the higher amorphous calcium carbonate gel polymerization degree. The local stress of each atom in the system is the driving force of the gelation transition. The presence of Si and Al components increases the atom's local stress and average charge, thus causing the increase of the energy barrier of CaCO3 polymerization and the activation energy of carbonation.

Unlocking the Potential of Chemically Modified Carbon Gels in Gallic Acid Adsorption.

This study deals with the preparation of adsorbents from a commercial xerogel by chemically modifying its surface with concentrated mineral acids and alkali metal chlorides, their physicochemical characterization, and their use as adsorbents for gallic acid in aqueous solution. Although there are publications on the use of carbon xerogels as adsorbents, we propose and study simple modifications that can change their chemical properties and, therefore, their performance as adsorbents. The adsorbate of choice is gallic acid and, to our knowledge, there is no history of its adsorption with carbon xerogels. The prepared adsorbents have a high specific surface area (347-563 m2 g-1), better pore development for samples treated with alkali metal chlorides than with mineral acids, and are more acidic than the initial xerogel (p.z.c range 2.49-6.87 vs. 7.20). The adsorption equilibrium is reached in <16 h with a kinetic constant between 0.018 and 0.035 h-1 for the pseudo-second-order model. The adsorption capacity, according to the Langmuir model, reaches 62.89 to 83.33 mg g-1. The adsorption properties of the commercial xerogel improved over a wide range of pH values and temperatures. The experimental results indicate that the adsorption process is thermodynamically favored.

Pore-scale prediction of the effective mass diffusivity and apparent permeability of carbon gels with adjustable nanoporous characteristics

To explore the structural effects on transport properties in carbon gels, an improved method has been introduced to regenerate their nanostructure and numerically illustrate the adjustability of their porous characteristics with the variation of synthesis parameters. Two lattice Boltzmann equations are applied to investigate the permeation and diffusion in the gel structures at the pore scale, and the apparent permeability is formulated to describe the total mass flux using the dusty gas model. The structural properties of the reconstructed models and calculated apparent permeabilities have been fully validated by various experiments. A decoupled analysis of the impact of structural parameters on transport properties demonstrates that increasing porosity and pore size, while decreasing geometric tortuosity, leads to more pronounced changes in intrinsic permeability compared to gas diffusivity. By utilizing a database that encompasses 240 reconstructed gels, a structural–functional relationship for transport properties in carbon gels could be proposed. Concerning the intrinsic permeability, a near quadratic relationship with the porosity and mean pore size, independent of particle size, could be concluded. For the nondimensional effective diffusivity, a power exponent of 1.85 associated with porosity is proposed, and its independence of pore size could be revealed. In addition, for gels with porosities under 0.65 and mean pore sizes less than 133 nm, diffusion supersedes permeation as the dominant term in total mass transfer, indicating that particle sizes have a more pronounced influence on the apparent permeability. The predictive model offers guidance for tailoring the transfer properties of carbon gels at the stage of preparation.

Facile Synthesis of Carbon-Based Inks to Develop Metal-Free ORR Electrocatalysts for Electro-Fenton Removal of Amoxicillin.

The electro-Fenton process is based on the generation of hydroxyl radicals (OH•) from hydroxide peroxide (H2O2) generated in situ by an oxygen reduction reaction (ORR). Catalysts based on carbon gels have aroused the interest of researchers as ORR catalysts due to their textural, chemical and even electrical properties. In this work, we synthesized metal-free electrocatalysts based on carbon gels doped with graphene oxide, which were conformed to a working electrode. The catalysts were prepared from organic-gel-based inks using painted (brush) and screen-printed methods free of binders. These new methods of electrode preparation were compared with the conventional pasted method on graphite supports using a binder. All these materials were tested for the electro-Fenton degradation of amoxicillin using a homemade magnetite coated with carbon (Fe3O4/C) as a Fenton catalyst. All catalysts showed very good behavior, but the one prepared by ink painting (brush) was the best one. The degradation of amoxicillin was close to 90% under optimal conditions ([Fe3O4/C] = 100 mg L-1, -0.55 V) with the catalyst prepared using the painted method with a brush, which had 14.59 mA cm-2 as JK and a H2O2 electrogeneration close to 100% at the optimal voltage. These results show that carbon-gel-based electrocatalysts are not only very good at this type of application but can be adhered to graphite free of binders, thus enhancing all their catalytic properties.

Scalable Synthesis of Stable Electrocatalyst for Oxygen Reduction Reaction

Carbon-based materials have been widely recognized as support material of choice for the oxygen reduction reaction due to their intriguing properties, such as high electrical conductivity, structural flexibility, and low cost. Platinum and its alloys supported on carbon are currently considered the benchmark catalysts for the oxygen reduction reaction (ORR) in Proton Exchange Membrane Fuel Cells (PEMFCs). Confining platinum within the pore system of mesoporous carbon prepared by hard-templating has proven to be an effective way to mitigate catalyst degradation in PEMFCs.[1] However, the challenge of template removal and the limited yield have hindered its practical application in industry. As a remedy, we establish a simple synthesis of carbon gels through sol-gel polymerization of resorcinol (R) and formaldehyde (F), ultimately resulting in graphitic mesoporous carbons.The synthesis process involves mixing resorcinol and formaldehyde in the presence of a basic catalyst, followed by heating for a certain period of time to obtain crosslinked gels.[2] Specific metal salts can be incorporated into the reaction to synthesize mesoporous and highly graphitic carbon spheres (GRF-Sphere) in a straightforward manner, without the need for hydrothermal steps, solvent exchanges, supercritical drying, or post-activation techniques. While conventional carbonized RF spheres are typically non-graphitic and microporous (Fig. 1.), modification of the synthesis route allows for the production of mesoporous, highly graphitic carbon spheres (GRF-Sphere) by taking advantage of the porogenic and graphitization effect of Fe(acac)2. Platinum nanoparticles with an average size of ca. 3 nm were deposited into the pores of GRF-spheres by incipient wetness impregnation followed by annealing at 750 °C. The specific activity of the Pt/GRF-Sphere catalyst for the ORR was found to be greater than 0.45 mA cm-2 Pt at 0.9 V vs. RHE, which in comparison with the literature indicates high catalytic activity.[3] The confinement of the active phase within the pores of the GRF-Spheres contributed to enhancing the stability of the catalyst, as confirmed by an accelerated stress test performed within the typical operating range of a PEMFC (0.6 - 1.0 VRHE). The Pt/GRF-Sphere was found to retain a significantly higher proportion of active surface area when compared to a reference Pt/Vulcan catalyst with similar platinum particle size (Fig. 1.).Furthermore, increasing the concentrations of resorcinol and formaldehyde by 25-fold resulted in the synthesis of a mesoporous and highly graphitic gel, namely GRF-Gel, at a substantial volume yield of70 g L-1, which underlines the potential for this process to be scaled up for industrial application. The ORR activity and stability of GRF-Gel in RDE are currently being investigated. Moreover, the electrochemical performance of this material will be evaluated in a single-cell PEMFC in collaboration with the group of Prof. Hubert Gasteiger (TU Munich).Overall, this research provides a promising and straightforward approach to synthesize highly graphitic mesoporous carbon materials using iron acetylacetonate as a porogen and graphitization catalyst. The method is based on the established preparation of RF-gels but includes iron salts. We have demonstrated that Pt/GRF-Sphere, which is produced by depositing Pt nanoparticles into the pore system of the GRF-Sphere, exhibits high activity and stability for the ORR. Given the simplicity and scalability of our synthesis procedure and the tailored morphology of these carbon materials, we believe that Pt/GRF-Sphere and Pt/GRF-Gel have great potential for industrial applications. Acknowledgement: We acknowledge the financial support from the German Federal Ministry for Economic Affairs and Energy (BMWi) in the framework of POREForm (project number 03ETB027F).

Cathode of Co9S8/NiMn-LDH with enhanced cycle stability and anode of carbon gels for asymmetric supercapacitors

Nickel‑manganese layered double hydroxide (NiMn-LDH) is used for supercapacitors due to its high redox activity and theoretical capacity, while with the disadvantages of low conductivity and unstable structure. Here, we report a Co9S8/NiMn-LDH composite electrode material with a core-shell heterostructure grown in situ on a carbon cloth (CC). NiMn-LDH nanosheets are uniformly and densely grown in the outer layer of Co9S8 nanorods, and this structure design makes full use of the high activity of NiMn-LDH. Meanwhile, the internal electric field formed at the heterogeneous interface is shown by density functional theory (DFT) calculations to effectively accelerate the diffusion of OH− in the electrode. The core-shell heterostructure makes it exhibit better electrochemical performance than NiMn-LDH as a positive electrode (178.7 mA h g−1 specific capacity at 1 A g−1, 80.6 % capacity retention after 5000 cycles). In addition, a carbon gels anode was prepared by the sol-gel method and subsequent carbonization steps, which has excellent performance (specific capacitance of 145.6 F g−1 at 1 A g−1). The assembled Co9S8/NiMn-LDH//C-gel asymmetric supercapacitor provides an energy density of 35.2 Wh kg−1 at 850 W kg−1. Further assembled into a quasi-solid-state flexible supercapacitor, two devices in series can light an LED lamp, showing its potential application prospects in energy storage systems.

Efficacy of Carbon Peel Laser in Acne Vulgaris in Skin of Color: A Single Center Prospective Study.

Acne vulgaris is a chronic disease of pilosebaceous units that affects approximately 80% of adult population. Despite various treatment modalities being reported, treating acne with minimal side effects is difficult. Specifically, topical carbon suspension combined with QsNdYAG laser treatment (carbon peel laser technique) has gained popularity recently for effective treatment of acne vulgaris. To study the efficacy of carbon peel laser technique in the management of acne vulgaris (Grade II-IV) in skin of color. A prospective observational study was done on 35 patients who presented with acne vulgaris Grade II-IV, who were poorly compliant to treatment with topical/systemic agents owing to side effects or failure of treatment, to meet patient's expectations. The patients were subjected to an initial topical application of carbon suspension (Cosderma Carbon gel) followed by treatment with quality switching neodymium yttrium aluminum garnet (Qs:NdYAG) laser in two modes (quasi long pulsed mode followed by Q switched mode 1064 nm). The treatment consisted of three sittings with intervals of 2 weeks. The patients were asked to avoid use of any topical/systemic medication for acne during this period. Significant reduction of erythematous and nodular acne lesions was noted after three sittings of "carbon peel laser technique". Among 35 patients, 28 (80%) showed >80% improvement and 7 (20%) showed 50%-80% improvement in skin lesions in the form of decrease in the number and size of lesions and extent of inflammation, with no patients nonresponsive to treatment. The postprocedure complications were minimal; 6 (20%) developed erythema, and 1 (3.3%) patient developed mild tolerable pain with no post inflammatory hyper/hypopigmentation. The postprocedure mean ISGA (Investigator Status Global Assessment) was 1.342 as compared with preprocedure mean ISGA of 3.657 with value of P <0.0001. Carbon peel laser technique is an effective method for the management of acne vulgaris in skin of color with minimal side effects and significant results.

Characterization of the pine biomass derived tannin–furfuryl carbon xerogels

A suitable and relatively low-cost route for synthesizing pine polyphenol-based carbon xerogels is reported. It is proposed to produce porous carbon xerogels by carbonization of organic xerogels synthesized primarily by polycondensation of pine-derived polyphenols (tannins and organosolv ethanol lignin) with furfuryl alcohol. The effect of the tannin:furfuryl alcohol weight ratio on the structural porosity, apparent density, and adsorption capacity of the carbon gels has been established. The carbon gel obtained at a tannin/furfuryl alcohol ratio of 1:1.5 is shown to have the largest BET surface area (585 m2/g) and pore volume (0.7 cm3/g). It has been found that this sample is capable of adsorbing up to 0.83 g/g of benzene vapour at a temperature of 25 °C. Using scanning electron microscopy, it has been established that the addition of lignin into the tannin/furfuryl organic xerogel increases the size of particles forming the carbon gel matrix and the pore size.

Microstructures and electrochemical characterization of graphene oxide/carboxymethylated cellulose nanofibril-derived hybrid carbon aerogels for freestanding supercapacitor electrodes

We herein report the morphological, thermal, electrical, and electrochemical properties of porous hybrid carbon aerogels prepared from carboxymethylated cellulose nanofibrils (c-CNF) and graphene oxide (GO, 1–10 wt %) via a facile process of freeze-drying, thermal stabilization, and carbonization at different temperatures of 800–1000 °C. During the carbonization, GO and c-CNF in the freeze-dried aerogel transformed into reduced GO (rGO) and porous carbon gel (CA), respectively. Morphological studies revealed that the porous hybrid carbon aerogels (rGO/CAs) had interconnected pores. The maximal electrical conductivity was achieved for the rGO/CA fabricated at the highest carbonization temperature of 1000 °C. With an increase in the amount of rGO, the electrical conductivity of the rGO/CAs increased to 0.91 S cm−1. For a three-electrode system in a PVA/H3PO4 gel electrolyte, the rGO/CA with 5 wt % rGO loading exhibited a high specific capacitance of 96.5 F g−1 at 0.5 A g−1. Also, the rGO/CA with 5 wt % rGO exhibited a rate capability of 10.3 % at 2 A g−1 and an energy density of 2.14 Wh kg−1 at a power density of 49.9 W kg−1. These results reveal that GO/c-CNF-derived hybrid carbon aerogels can be utilized as a potential material for the free-standing electrode of supercapacitors.

Clarification of the Effects of Oxygen Containing Functional Groups on the Pore Filling Behavior of Discharge Deposits in Lithium–Air Battery Cathodes Using Surface-Modified Carbon Gels

In lithium–air batteries (LABs), controlling the characteristics of the Li2O2 deposited during discharging can lead to the reduction of the large overpotential required for charging. The large overpotential is one of the most significant problems that needs to be solved to improve the cycle performance of LABs. Here, we focused on the effects of functional groups in the cathode carbon on the characteristics of the Li2O2 deposited during discharging and the cathode performance of LABs. In this study, 4 types of carbon gels (CGs) were prepared using different treatment methods to modify their surface properties. The types and amounts of oxygen-containing functional groups (OCFGs) existing within the CGs were clarified along with the number of edge H’s by a high-sensitivity temperature-programmed desorption (TPD) technique. The results of N2 adsorption analysis of discharged CGs suggested that, by increasing the number of OCFGs from 0.40 to 1.80 mmol g–1 through acid treatment, the ratio of Li2O2 deposited within the mesopores of the porous carbon particles can be increased from 1% to 60%. This significant change in the manner of Li2O2 deposition led to the reduction of the charging overpotential. Side reactions that are thought to deteriorate cycle performance tended to proceed in CGs having a large number of OCFGs. This negative effect could be reduced by removing carboxyl groups in the CGs through simple heat treatment at 300 °C in an inert atmosphere. Our study clarified the critical roles of OCFGs in the cathode during the discharging and charging of LABs. The obtained knowledge can be utilized for the development of a high-performance cathode for LABs.

A novel characterization of alginate-attapulgite-calcium carbonate (AAC) gel adsorption in bacterial biodegradation of used engine oil (UEO)

Biodegradation of used engine oil (UEO) that pollutes the environment is attracting increasing attention. The aim of this study was to characterize the adsorption of used engine oil (UEO) and the immobilization of UEO biodegraders in Ochrobacterium intermedium LMG 3301 and Ochrobacterium intermedium LMG 3301 plus Bacillus paramycoides MCCC1A04098 (BC) using alginate-attapulgite-calcium carbonate (AAC). Twenty AAC beads were tested separately in 20 mL of soil water extract (SWE) and hexane containing 1% UEO for their adsorptive capacities of UEO in 50-mL capped flasks. The results showed that the UEO removal efficiency (%RE) was bead-number dependent, recording a maximum of 83 ± 0.32% in SWE, and 11.50 ± 0.52% in hexane correlating with the highest number of AAC-granules (20 beads). The 1st order kinetics in SWE showed a UEO adsorption rate, K1 (h−1), of 0.11–0.15 h−1 correlating with 20 AAC-granules and 1, 2, 3 and 4% (w/v) UEO. The intra-particle diffusion kinetic model suggested that intra-diffusion was the main mode of mass transfer in AAC granules. The microscopic study and 2,3,5-triphenyltetrazolium chloride (TTC) positive stain showed that bacteria grew well in AAC. This result demonstrates that this matrix can be applied in the formulation of novel adsorptive granular formulas for bioremediation of UEO.

Improving porous properties of activated carbon from carbon gel by the OTA method.

High-surface-area microporous-mesoporous carbons were produced from carbon gel by applying the three consecutive steps of air oxidation, thermal treatment, and activation (the OTA method) to the gel. The formation of mesopores occurs both inside and outside the nanoparticles which form the carbon gel, while micropores are predominantly created within the nanoparticles. The OTA method offered a greater increase in pore volume and BET surface area of the resulting activated carbon in comparison with conventional CO2 activation either under the same activation conditions or at the same degree of carbon burn-off. Under the best preparation conditions, the maximum values of micropore volume, mesopore volume, and BET surface area achievable using the OTA method were found to be 1.19 cm3 g-1, 1.81 cm3 g-1, and 2920 m2 g-1, respectively at a 72% carbon burn-off. The larger increase in porous properties of activated carbon gel prepared by the OTA method over those based on conventional activation stems from the effects of the oxidation and heat treatment steps of the OTA method that could produce a large number of reaction sites which lead to efficient pore formation during the following CO2 activation process.

New insights into the early stage nucleation of calcium carbonate gels by reactive molecular dynamics simulations.

The precipitation of calcium carbonate (CaCO3) is a key mechanism in carbon capture applications relying on mineralization. In that regard, Ca-rich cementitious binders offer a unique opportunity to act as a large-scale carbon sink by immobilizing CO2 as calcium carbonate by mineralization. However, the atomistic mechanism of calcium carbonate formation is still not fully understood. Here, we study the atomic scale nucleation mechanism of an early stage amorphous CaCO3 gel based on reactive molecular dynamics (MD) simulations. We observe that reactive MD offers a notably improved description of this reaction as compared to classical MD, which allows us to reveal new insights into the structure of amorphous calcium carbonate gels and formation kinetics thereof.

Synthesis and electrochemical properties of ZnMn2O4 with hollow porous panpipe-like structure as anode material for Li-ion battery

In this work, ZnMn2O4 anode material with excellent lithium storage performance is prepared by combining the carbon gel–combustion method and the hard template strategy (a polypropylene membrane with high porosity). The as–obtained ZnMn2O4 sample has a hollow panpipe–like structure with rich pore characteristics. The phase composition, micro–nano structure, crystallinity, pore size distribution, specific surface area, element distribution and valence state of the samples are systematically tested and analyzed by XRD, ICP–AES, FESEM, TEM, HRTEM, N2 adsorption/desorption measurement and XPS. When assembled into a half–cell with metallic lithium as the counter electrode, the ZnMn2O4 electrode material exhibits higher reversible capacity (under low and high current densities), excellent cycle stability and rate capability with better dynamic properties compared with the ZnMn2O4 sample obtained without using the organic template agent. Porous structure characteristics, small particle size, high specific surface area, high crystallinity and special micro–nano structure help to effectively improve the kinetic properties and structural stability of the electrode material during charge/discharge processes for achieving high energy and power densities.

Resorcinol-based carbon xerogel/ZnO composite for solar-light-induced photodegradation of sulfamerazine

Recently, the release of antibiotics, such as sulfonamides, into the environment has raised significant concern due to the potential creation of antibiotic-resistant bacteria. Thus, the development of remediation technologies for effluents containing such compounds is of utmost urgency. In this context, this work evaluated the creation of a resorcinol-based carbon xerogel/zinc oxide photocatalyst (XC/ZnO) to efficiently promote the photodegradation of the antibiotic known as sulfamerazine in aqueous media. The employment of this carbonaceous structure as a co-catalyst is justified by its high surface area and electrical conductivity. The methodology used in the synthesis of the composites was a simple one-pot reaction, combining the simultaneous precipitation of zinc oxide and polycondensation of the resorcinol-based carbon gel. Regarding the composites' characterization, X-ray diffractometry confirms that the composites have the Wurtzite structure of the zinc oxide, whereas the carbon xerogel formation is evidenced by the infrared, diffuse reflectance, and X-ray photoelectron spectroscopies. Morphology-wise, the XC/ZnO is arranged as nodular particle agglomerates, with particles between 500 nm and 50 nm. The photocatalytic tests under simulated solar radiation show that the composites developed are superior to the pure oxide in the photodegradation of sulfamerazine, as all XC/ZnO materials developed achieved higher apparent reaction rate constants (kapp) than pure zinc oxide, with the XC/ZnO 0.5 material obtaining a kapp 75% higher than the one observed for the ZnO sample. Furthermore, the chronoamperometry tests confirmed that the optimized composite (XC/ZnO 0.5) has a greater capacity for photocurrent generation when compared to pure zinc oxide. Therefore, the modification proposed was successful to enhance the photodegradation of sulfamerazine in aqueous media, highlighting the viability of the composites developed for photocatalytic applications.

Synthesis and Properties of Carbon Gels Based on Larch Bark Tannins and Hydrolysis Lignin

Synthesis and Properties of Carbon Gels Based on Larch Bark Tannins and Hydrolysis Lignin

Self-activated, urea modified microporous carbon cryogels for high-performance CO2 capture and separation

Conventionally, porous carbons were synthesized using corrosive chemical activating agents. On contrary, we designed a single-step synthesis method for the preparation of a series of self-activated heteroatom (N)-doped carbon cryogels from potassium hydrogen phthalate (KHP) and urea at various temperatures (700–1000 °C), in the absence of any activating agent. To highlight the effectiveness of N-doping in porosity generation and CO2 adsorption/separation, a comparative analysis was drawn with a series of undoped carbon cryogels. Notably, the N-doped cryogels exhibit a highly porous structure with remarkable specific surface area (SSA; 2084 m2 g−1), micropore volume (1.1806 cm3 g−1), well-defined pore size distribution, and abundant narrow micropores (<1.04 nm). Additionally, a considerable mechanical strength (compressive strength = 0.621 MPa and compressive modulus = 8.86 MPa) was also observed. Moreover, the porous cryogel endowed with sufficient pyrrolic nitrogen content (≈51.4 at %) lead to high CO2 adsorption (280.57 mg/g at 273 K and 171.31 mg/g at 298 K at 1 bar) and an excellent ideal adsorbed solution theory (IAST)-based CO2/N2 selectivity (≈115) at 273 K, surpassing the CO2 adsorption/separation performance of previously reported N-doped carbons and resorcinol-based carbon gels. Furthermore, the moderate heat of adsorption (36.109 kJ mol−1) and stable cyclic behavior of CO2 adsorption-desorption under flue gas conditions (i.e., 15% CO2/85% N2) unveils the physisorption nature of adsorption which governs the energy-effective regeneration process. Summarizing, the present work demonstrates the successful fabrication of highly porous carbon cryogels as efficient CO2 adsorbents, thereby opening new synthetic avenues for self-activating porous carbon formation.

A review on the development of a porous carbon-based as modeling materials for electric double layer capacitors

Carbon electrodes are a key factor for electric double layer capacitors (EDLCs). Carbon gels have high porosity with a controllable pore structure by changing synthesis conditions and modifying preparation processing to improve the electrochemical performance of EDLCs. This review summarizes the preparation of carbon gels and their derivatives, the criteria to synthesize high surface area in each process, the development by some carbon forms, and EDLC applications. Porous carbons are also prepared as model materials by concentrating on how pore structure increases electrochemical capacitance, such as electronic and ion resistance, the tortuosity of pore channel, suitable micropore and mesopore sizes, and mesopore size distribution. This review emphasizes the significance of pore structures as the key factor to allow for the design of suitable pore structures that are suitable as the carbon electrode for EDLCs.