Micro-mesoporous Carbon Research Articles

MOF derived porous Fe-Cu@carbon catalyst for the degradation of bisphenol A through a persulfate-based advanced oxidation process

A calcination strategy based on the use of mixed MOF HKUST-1/MIL-100 as precursor was used for the obtention of a porous carbon composite (C-HKUST-1/MIL-100) containing iron-copper bimetallic particles within it. The prepared carbon was characterized by XRD, SEM, EDS spectroscopy and N2 adsorption-desorption, confirming the obtention of a micro-mesoporous carbon with Fe-Cu particles homogenously distributed within the structure. For comparison, Cu and Fe-carbons (C-HKUST-1 and C-MIL-100, respectively) were also prepared from the corresponding HKUST-1 and MIL-100 MOFs, respectively. The catalytic performance of the developed carbons as heterogeneous catalysts for persulfate-based advanced oxidation degradation of bisphenol A was evaluated. The Fe-Cu@carbon showed the best catalytic performance, leading to a total BPA degradation after just 10 min of reaction, which was closely related to the synergistic effect of iron and copper. The effect of some key parameters including initial pH value, PS concentration and catalyst dosage was investigated using the Fe-Cu@carbon. In addition, the developed carbon showed good reusability, with no apparent loss in BPA degradation, after five cycles and the ability to treat real water samples, with the advantage that the recovery process after degradation is facilitated thanks to its magnetic properties.

Sub-millisecond lithiothermal synthesis of graphitic meso–microporous carbon

Porous carbons with concurrently high specific surface area and electronic conductivity are desirable by virtue of their desirable electron and ion transport ability, but conventional preparing methods suffer from either low yield or inferior quality carbons. Here we developed a lithiothermal approach to bottom–up synthesize highly meso–microporous graphitized carbon (MGC). The preparation can be finished in a few milliseconds by the self-propagating reaction between polytetrafluoroethylene powder and molten lithium (Li) metal, during which instant ultra-high temperature (>3000 K) was produced. This instantaneous carbon vaporization and condensation at ultra-high temperatures and in ultra-short duration enable the MGC to show a highly graphitized and continuously cross-coupled open pore structure. MGC displays superior electrochemical capacitor performance of exceptional power capability and ultralong-term cyclability. The processes used to make this carbon are readily scalable to industrial levels.

Optimization of Carbon-Defect Engineering to Boost Catalytic Ozonation Efficiency of Single Fe─N4 Coordination Motif.

Carbon-defect engineering in single-atom metal-nitrogen-carbon (M─N─C) catalysts by straightforward and robust strategy, enhancing their catalytic activity for volatile organic compounds, and uncovering the carbon vacancy-catalytic activity relationship are meaningful but challenging. In this study, an iron-nitrogen-carbon (Fe─N─C) catalyst is intentionally designed through a carbon-thermal-diffusion strategy, exposing extensively the carbon-defective Fe─N4 sites within a micro-mesoporous carbon matrix. The optimization of Fe─N4 sites results in exceptional catalytic ozonation efficiency, surpassing that of intact Fe─N4 sites and commercial MnO2 by 10 and 312 times, respectively. Theoretical calculations and experimental data demonstrated that carbon-defect engineering induces selective cleavage of C─N bond neighboring the Fe─N4 motif. This induces an increase in non-uniform charges and Fermi density, leading to elevated energy levels at the center of Fe d-band. Compared to the intact atomic configuration, carbon-defective Fe─N4 site is more activated to strengthen the interaction with O3 and weaken the O─O bond, thereby reducing the barriers for highly active surface atomic oxygen (*O/*OO), ultimately achieving efficient oxidation of CH3SH and its intermediates. This research not only offers a viable approach to enhance the catalytic ozonation activity of M─N─C but also advances the fundamental comprehension of how periphery carbon environment influences the characteristics and efficacy of M─N4 sites.

Gradient Pores Enhance Charge Storage Density of Carbonaceous Cathodes for Zn-Ion Capacitor.

Engineering carbonaceous cathode materials with adequately accessible active sites is crucial for unleashing their charge storage potential. Herein, activated meso-microporous shell carbon (MMSC-A)nanofibers are constructed to enhance the zinc ion storage density by forming a gradient-pore structure. A dominating pore size of 0.86nm is tailored to cater for the solvated [Zn(H2 O)6 ]2+ . Moreover, these gradient porous nanofibers feature rapid ion/electron dual conduction pathways and offer abundant active surfaces with high affinity to electrolyte. When employed in Zn-ion capacitors (ZICs), the electrode delivers significantly enhanced capacity (257 mAh g-1 ), energy density (200Wh kg-1 at 78W kg-1 ), and cyclic stability (95% retention after 10000 cycles) compared to nonactivated carbon nanofibers electrode. A series of in situ characterization techniques unveil that the improved Zn2+ storage capability stems from size compatibility between the pores and [Zn(H2 O)6 ]2+ , the co-adsorption of Zn2+ , H+ , and SO4 2- , as well as reversible surface chemical interaction. This work presents an effective method to engineering meso-microporous carbon materials toward high energy-density storage, and also offers insights into the Zn2+ storage mechanism in such gradient-pore structures.

Meso-Microporous Carbon Nanofibrous Aerogel Electrode Material with Fluorine-Treated Wood Biochar for High-Performance Supercapacitor.

A supercapacitor is an electrical energy storage system with high power output. With worldwide awareness of sustainable development, developing cost-effective, environmentally friendly, and high-performance supercapacitors is an important research direction. The use of sustainable components like wood biochar in the electrode materials for supercapacitor uses holds great promise for sustainable supercapacitor development. In this study, we demonstrated a facile and powerful approach to prepare meso-microporous carbon electrode materials for sustainable and high-performance supercapacitor development by electrospinning polyacrylonitrile (PAN) with F-treated biochar and subsequent aerogel construction followed by stabilization, carbonization, and carbon activation. The resultant carbon nanofibrous aerogel electrode material (ENFA-FBa) exhibited exceptional specific capacitance, attributing to enormously increased micropore and mesopore volumes, much more activated sites to charge storage, and significantly greater electrochemical interaction with electrolyte. This electrode material achieved a specific capacitance of 407 F/g at current density of 0.5 A/g in 1 M H2SO4 electrolyte, which outperformed the state-of-the-art specific capacitance of biochar-containing electrospun carbon nanofibrous aerogel electrode materials (<300 F/g). A symmetric two-electrode cell with ENFA-FBa as electrode material showed an energy density of 11.2 Wh/kg at 125 W/kg power density. Even after 10,000 cycles of charging-discharging at current density of 10 A/g, the device maintained a consistent coulombic efficiency of 53.5% and an outstanding capacitance retention of 91%. Our research pointed out a promising direction to develop sustainable electrode materials for future high-performance supercapacitors.

Upcycling of aureomycin hydrochloride residue into highly meso-microporous carbon with remarkable adsorption capacity for benzene capture

The exploration of high-value utilization of antibiotic bacteria residues is of great importance at the environmental and resource levels. In this study, we report an aureomycin hydrochloride residue-derived activated carbon and its application in the adsorption of hazardous benzene. Self-N-doped activated carbon with excellent benzene adsorption properties was prepared by K2CO3-assisted activation pyrolysis using aureomycin hydrochloride residue as carbon and nitrogen sources. It is found that the pore structure and the benzene adsorption behavior could be optimized through regulating the mass ratio of K2CO3 to carbon (mK2CO3/mC) and the activation temperature. Under the pyrolysis conditions of mK2CO3/mC = 3:1 and 800 ºC, the specific surface area and total pore volume of the as-prepared carbon reached 1564 m2 g−1 and 0.70 cm3 g−1, respectively, whereas those of the micropores were 1440 m2 g−1 and 0.48 cm3 g−1, respectively, implying that the proportion of micropores reached 68.6%. The adsorption capacity of benzene based on the optimal adsorbent (AHRC-3PC-800) was as high as 1303 mg g−1 at 25 ºC and relative pressure (P/P0) of 0.9–1. Therefore, the aureomycin hydrochloride residue-based activated carbon adsorbent has a broad application prospect in the removal of volatile organic compounds.

Adsorption of Methane Vapors on a Micro-Mesoporous Carbon Adsorbent During Long-Term Storage of Liquefied Natural Gas

Adsorption of Methane Vapors on a Micro-Mesoporous Carbon Adsorbent During Long-Term Storage of Liquefied Natural Gas

Micro-mesoporous carbon nanofibers loaded with sulfur as a self-supported cathode for high-performance Li-S batteries

Self-supported carbon fibers with hierarchical porous structures regulated by zinc salt and copper salt were prepared through electrospinning technology, and sulfur loaded carbon fibers were obtained through sulfur vapor deposition method. Small molecular sulfur (S2-S4) and cyclic sulfur (S8) were encapsulated effectively in hierarchical pores by this way, both of them could run stably in carbonate electrolyte. Due to the three-dimensional conductive structure and suitable pore structure of the carbon fibers, the self-supported S/MCNF-ZnCu cathode exhibits high capacity, excellent cycling stability and out-standing rate capacity. The reversible capacity after 100 cycles at 0.2 A g−1 based on the mass of cathode is 520 mAh g−1, corresponding to the capacity retention rate of 98.4 %. The reversible capacity after 1000 cycles at 1.0 A g−1 is 429 mAh g−1, with a capacity loss of approximately 0.01 % per cycle. Even at the sulfur loading of 4 mg cm−2, the cathode shows a stable capacity of nearly 500 mAh g−1 at 0.1 A g−1, provides a novel and efficient strategy for the next generation of high-performance batteries.

Hierarchical micro-mesoporous carbon firmly confined iodine for high performance zinc-iodine batteries

Aqueous rechargeable zinc-iodine battery is a hot research topic in energy storage devices. However, limited by iodine dissolution and polyiodide ions shuttle, zinc-iodine cells suffer from severe degradation of the performance. In this paper, we realized high-performance aqueous zinc-iodine batteries by anchoring iodine on hierarchical micro-mesoporous carbon nanospheres (HMMC NSs) with homogeneous pore distribution. The unique hierarchical micro-mesoporous structure provides high immobilization capacity, effectively inhibiting iodine dissolution and polyiodide ions shuttling. When applying the HMMC-I2 NSs as the cathode of zinc-iodine battery, it shows superior cycling capability.

"Sweetwoods" Lignin as Promising Raw Material to Obtain Micro-Mesoporous Carbon Materials.

Biorefineries with the significant amounts of lignin as a by-product have a potential to increase business revenues by using this residue to produce high value-added materials. The carbon materials from biomass waste increases the profitability of the production of porous carbon used for sorbents and energy production. The purpose of this research is to study the chemical properties of lignin from "Sweetwoods" biorefinery as well as to characterize lignin carbonizates and activated carbons synthesized from them. This paper describes the effect of carbonization conditions (thermal or hydrothermal) on the properties of activated carbon material. It can be concluded that, depending on the carbonization method, the three-dimensional hierarchical porous structure of activated carbon materials based on "Sweetwoods" lignin, has micro- and mesopores of various sizes and can be used for number of purposes: both for high-quality sorbents, catalysts for electrochemical reduction reactions, providing sufficient space for ion mass transfer in electrodes for energy storage and transfer.

Activated three-dimensionally ordered micromesoporous carbons for CO2 capture

Three-dimensionally ordered micromesoporous carbon (3DOmm) has been studied recently as a potential sorbent for CO2 capture at higher pressures. However, the as-synthesized material usually has a low microporous fraction, which could significantly limit CO2 uptake. Herein, we showed that microporosity in 3DOmm carbon can be increased by physical activation, substantially improving its CO2 capture performance in the wide pressure range. The highly porous activated 3DOmm carbons, having amorphous structure, were prepared with ordered spherical mesopores of diameter 22.7–24.7 nm and ultramicropores in the walls of diameter 0.41–0.55 nm. Physical activation was performed by exposing the post-synthesized 3DOmm carbon to high temperatures of 973–1173 K under a CO2 flow for 30 min. The activation procedure did not show any visible destruction of the ordered mesoporous structure in the 3DOmm carbon. However, it had a significant impact on micropore and mesopore volumes and the specific surface area, which in turn affected the CO2 adsorption capacity of the carbons. Accordingly, after activation at 973 K, the micropore volume of 0.23 cm3/g, the mesopore volume of 3.70 cm3/g and the specific surface area of 1058 m2/g in the 3DOmm carbon increased to 0.27 cm3/g, 3.94 cm3/g and 1462 m2/g, respectively. Further increase in activation temperature led to decreasing pore values due to widening and shrinking of the thin carbon walls in the 3DOmm carbon. The 3DOmm carbon activated at 973 K had the highest micropore and mesopore volumes and the highest CO2 adsorption performance over the whole pressure range (3.19 mmol/g at 273 K and 100 kPa; 11.18 mmol/g at 298 K and 2 MPa and 0.38 mmol/g under flue 15% CO2/85% N2 gas conditions at 298 K). All 3DOmm carbons showed fast kinetics, high selectivity for CO2 over N2 (33.2–51.5), the excellent regenerative ability and isosteric heats (18.9–29.2 kJ/mol), indicating physical adsorption.

Unraveling the roles of microporous and micro-mesoporous structures of carbon supports on iron oxide properties and As (V) removal performance in contaminated water

This study investigates the impact of microporous (SP–C) and micro-mesoporous carbon (DP-C) supports on the dispersion and phase transformation of iron oxides and their arsenic (V) removal efficiency. The research demonstrates that carbon-supported iron oxide sorbents exhibit superior As(V) uptake capacity compared to unsupported Fe2O3, attributed to reduced iron oxide crystallite sizes and As(V) adsorption on carbon supports. Maximum As(V) uptake capacities of 23.8 mg/g and 18.9 mg/g were achieved for Fe/SP-C and Fe/DP-C at 30 wt% and 50 wt% iron loading, respectively. The study reveals a nonlinear relationship between As(V) sorption capacity and iron oxide crystallite size after excluding As(V) adsorption capacity on carbon supports, suggesting the iron oxide phase (Fe3O4) plays a role in determining adsorption capacity. Iron oxide-loaded DP-C sorbents exhibit faster adsorption rates at low As(V) concentrations (5 mg/L) than SP-C sorbents due to their bimodal pore structure. Adsorption behavior varies at higher As(V) concentrations (45 mg/L), with Fe/DP-C reaching maximum capacity more slowly due to limited available adsorptive sites. All adsorbents maintained near-complete As(V) removal efficiency over five cycles. The findings provide insights for designing more efficient adsorbents for As(V) removal from contaminated water sources.

Cobalt Phthalocyanine-Doped Polymer-Based Electrocatalyst for Rechargeable Zinc-Air Batteries.

Rechargeable zinc-air batteries (RZAB) have gained significant attention as potential energy storage devices due to their high energy density, cost-effectiveness, and to the fact that they are environmentally safe. However, the practical implementation of RZABs has been impeded by challenges such as sluggish oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), including poor cyclability. Herein, we report the preparation of cobalt- and nitrogen-doped porous carbon derived from phloroglucinol-formaldehyde polymer networks with 2-methyl imidazole and cobalt phthalocyanine as precursors for nitrogen and cobalt. The CoN-PC-2 catalyst prepared in this study exhibits commendable electrocatalytic activity for both ORR and OER, evidenced by a half-wave potential of 0.81 V and Ej=10 of 1.70 V. Moreover, the catalyst demonstrates outstanding performance in zinc-air batteries, achieving a peak power density of 158 mW cm-2 and displaying excellent stability during charge-discharge cycles. The findings from this study aim to provide valuable insights and guidelines for further research and the development of hierarchical micro-mesoporous carbon materials from polymer networks, facilitating their potential commercialisation and widespread deployment in energy storage applications.

Self-Assembly and the Properties of Micro-Mesoporous Carbon.

This study introduces a new approach for constructing atomistic models of nanoporous carbon by randomly distributing carbon atoms and pore volumes in a periodic box and then using empirical and ab initio molecular simulation tools to find the suitable energy-minimum structures. The models, consisting of 5000, 8000, 12000, and 64000 atoms, each at mass densities of 0.5, 0.75, and 1 g/cm3, were analyzed to determine their structural characteristics and relaxed pore size distribution. Surface analysis of the pore region revealed that sp atoms exist predominantly on surfaces and act as active sites for oxygen adsorption. We also investigated the electronic and vibrational properties of the models, and localized states near the Fermi level were found to be primarily situated at sp carbon atoms through which electrical conduction may occur. Additionally, the thermal conductivity was calculated using heat flux correlations and the Green-Kubo formula, and its dependence on pore geometry and connectivity was analyzed. The behavior of the mechanical elasticity moduli (Shear, Bulk, and Young's moduli) of nanoporous carbons at the densities of interest was discussed.

Built-in ultrafine CoS2 catalysis in confined ordered micro-mesoporous carbon nanoreactors for high-performance Li–S batteries

Constructing high-performance cathode host materials which can eliminate the dissatisfactory utilization of sulfur, the sluggish redox kinetics, and the lithium polysulfide (LiPSs) shuttle effect is highly desirable for the development of lithium-sulfur (Li–S) batteries. Recently, the porous carbon nanoreactors have received significant attention owing to unique spatial structure and customizable reaction sites. Whereas, the disordered pore distribution as well as surface catalysis in these hosts still restrict the performance of Li–S batterie. Herein, a synthesis of built-in ultrafine CoS2 catalysis in confined ordered micro-mesoporous carbon (OMMC) nanoreactors is proposed to accelerate LiPSs conversion. Due to high surface areas, protective OMMC shell, great electronic conductivity, and high-efficiency active sites, the synthetic nanoreactor shows exceptional physical confinement, satisfactory chemical anchoring, as well as excellent electrocatalysis for LiPSs. As expected, the S/CoS2@OMMC cathodes achieved excellent cyclic stability (615 mAh g−1 at 1.0 C after 1000 cycles with an ultralow capacity decay of 0.032% per cycle) and outstanding rate performance (655 mAh g−1 at 5.0 C).

Ultra-high-performance aluminum-based hybrid supercapacitors prepared for nitrogen-doped micro-mesoporous carbon sphere

Aluminum-based devices are promising candidates for the next generation of energy storage due to the advantages of high energy density, high safety, and low cost. The aluminum ion batteries (AIBs) are based on the electrochemical intercalation/deintercalation reactions against the electrodes, but the selection of the cathode is limited to the present. The cathode reactions of cation-type AIBs are plagued by the poor kinetics of solid-state diffusion from high charge density of Al3+ and anion-type AIBs show poor capacity due to the intercalation of large-sized chloroaluminate (AlCl4−) active ions into the cathode. Here, we deliberately adopted a hybrid capacitor-battery mechanism and employed a nitrogen-doped micro-mesoporous carbon sphere of a high specific area as the cathode and aluminum as the anode to construct an aluminum-based energy storage device. After optimization, it exhibits an excellent discharge capacity of 224 mA h g−1 at a current density of 300 mA g−1, and exceptional cycling performance with a discharge capacity as high as 114 mA h g−1 at 10 A g−1 after 35000 cycles. The ultra-high-performance aluminum-based hybrid supercapacitor (Al-HSC) may lead to a new direction for the development of aluminum-based energy storage devices.

N, O co-doped micro-mesoporous carbon obtained by sustainable conversion of biomass waste for supercapacitors

N, O co-doped micro-mesoporous carbon obtained by sustainable conversion of biomass waste for supercapacitors

Hoya-like Hierarchical Porous Architecture as Multifunctional Phosphorus Anode for Superior Lithium-Sodium Storage.

Designing nanostructured hosts with the merits of high conductivity, strong trapping ability, and long-term durability to improve the insulating nature and extreme volume change of red phosphorus (RP) is a promising option for the development of high-performance lithium/sodium-ion batteries (LIBs/SIBs). Here, a multifunctional RP immobilizer is proposed and fabricated, which comprises a nitrogen-doped hollow MXene sphere (NM) planted with the dual-sided porous carbon network (DCNM). In such a configuration, the highly conductive macroporous NM not only facilitates fast electron transport but also acts as the capturing center to entrap polyphosphide through strong chemical adsorption, while the uniformly distributed micromesoporous carbon network in or out of the sphere provides reliable RP accommodation and alleviates the volume expansion, as well as creates interpenetrating ion diffusion and electron transport channels. Benefiting from the synergistic effect of the triple-shelled architecture and the exclusive restraint, the Hoya-like DCNM@RP anode exhibits significantly enhanced electrochemical performances for LIBs and SIBs, delivering a combination of high reversible capacity, splendid rate properties, and extended cycling performance: up to 1800 cycles with 0.01% per cycle capacity decay for LIBs and 0.024% per cycle over 1000 cycles for SIBs at 2 C.

Utilization of single biomass-derived micro-mesoporous carbon for dual-carbon symmetric and hybrid sodium-ion capacitors

Single biomass precursor-derived AJPC-M as dual electrodes in aqueous and non-aqueous systems for symmetric and hybrid SICs.

Porous carbons prepared from a novel hard wood composite waste for effective adsorption of Pb(ii) and Cd(ii) ions.

In our previous investigations, a hard wood composite (HWC) was formulated by adding rice straw, as a filler to the recycled polystyrene foam waste at mass ratio (50/50) at 170 °C and pressed under 40 kPa. Here, the disposed HWC product as a model scrap was applied for production of porous carbons enclosed with graphene sheets. To attain this approach, HWC was hydrothermally carbonized (S1) followed by either post-heat treatment (S2) or potassium hydroxide (KOH, S3) activation at 750 °C for 2 hours. The properties of prepared samples were evaluated using SEM, ATR-IR, and porosity measurements. The adsorption performance of the obtained porous carbons toward removal of lead (Pb(ii)) and cadmium (Cd(ii)) ions from aqueous solutions was investigated under different operating conditions like contact time, initial pH, initial metal ions concentration and adsorbent dose. Kinetic models such as pseudo-first order, pseudo-second order and intraparticle diffusion were used to analyze the adsorption data. Langmuir, Freundlich, Dubinin-Radushkevich and Redlich-Peterson isotherms were applied. Thermodynamics and regeneration studies were performed. The sample (S3) comprised a micro-mesoporous carbon structure encompassed by graphene sheets, with the largest total surface area (422 m2 g-1) and adsorption capacities for Pb(ii) and Cd(ii) ions of 207.9 and 119.6 mg g-1, respectively. The experimental adsorption data were best elucidated using Langmuir and pseudo second-order kinetic models. Thermodynamic experiments confirmed that adsorption is an endothermic and spontaneous process. Conclusively, the investigated HWC waste is a promising carbonaceous precursor for preparing effective porous graphene-carbons used in the removal heavy metals from their aqueous stream.