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In this study, carbon foam derived from silicon‐containing arylacetylene resin (CFPSA) was prepared by using silicon‐containing arylacetylene (PSA) resin as the carbon precursor and polyurethane (PU) foam as the organic sacrificial template. CFPSAs with diverse apparent densities were prepared through the simple impregnation of PU foam with PSA resin solutions of varying concentrations. Their structures, such as the pore morphology; chemical composition; thermal stability; compression properties, and electromagnetic interference (EMI) shielding effectiveness (SE), were characterized. The results indicate that with an increase in the PSA resin concentration, the skeleton of CFPSA becomes thicker, the pore size slightly increases, the apparent density increases, the compressive strength increases, and the EMI SE slightly reduces. CFPSA‐10's apparent density is 0.032 g/cm3, its 5% thermal weight loss temperature (Td5) in an air atmosphere is 642°C, its thermal conductivity is 38.1 mW/m K, its specific compression strength is 2.45 MPa/g cm3, and its specific EMI SE divided by thickness (SSE/t) is 2367 dB cm2/g. CFPSA exhibits lightweight and antioxidant properties, as well as excellent electromagnetic interference shielding performance, presenting great potential for application in aerospace and other fields. [ABSTRACT FROM AUTHOR]

Multiform NiO nanowalls with a high specific surface area were constructed in situ on carbon foam (CF) to construct NiO@CF/OD composite phase change materials (CPCMs). The synthesis mechanism, microstructures, thermal management capability, and photothermal conversion of NiO@CF/OD CPCMs were systematically studied. Additionally, the collaborative enhancement effects of CF and multiform NiO nanowalls on the thermal properties of OD PCMs were also investigated. NiO@CF not only maintains the porous 3D network structure of CF, but also effectively prevents the aggregation of NiO nanosheets. The chemical structures of NiO@CF/OD CPCMs were analyzed using XRD and FTIR spectroscopy. When combined with CF and NiO nanosheets, OD has high compatibility with NiO@CF. The thermal conductivity of NiO@CF/OD-L CPCMs was 1.12 W/m·K, which is 366.7% higher than that of OD. The improvement in thermal conductivity of CPCMs was theoretically analyzed according to the Debye model. NiO@CF/OD-L CPCMs have a photothermal conversion efficiency up to 77.6%. This article provided a theoretical basis for the optimal design and performance prediction of thermal storage materials and systems. [ABSTRACT FROM AUTHOR]

Developing materials for efficient energy storage and effective electromagnetic interference (EMI) shielding is crucial in modern technology. This study explores the synthesis and characterization of carbonaceous shape-stabilized octadecane/MWCNT (multi-walled carbon nanotube) composites, utilizing activated carbon, expanded graphite or ceramic carbon foam, as shape stabilizers for phase change materials (PCMs) to enhance thermal energy storage and EMI shielding, for energy-efficient and advanced applications. The integration of octadecane, a phase change material (PCM) with carbonaceous stabilizers ensures the material's stability during phase transitions, while MWCNTs contribute to improved thermal storage properties and EMI shielding capabilities. The research aims to develop novel composites with dual functionality for thermal storage and EMI shielding, emphasizing the role of carbon matrices and their MWCNT composites. SEM and CT microtomography analyses reveal variations in MWCNT incorporation across the matrices, influenced by surface properties and porosity. Leaching tests, infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) confirm the composite's stability and high latent heat storage. The presence of nanotubes enhances the thermal properties of octadecane and ΔH values almost reached their theoretical values. EMI shielding effectiveness measurements indicate that the composites show improved electric properties in the presence of MWCNTs. [ABSTRACT FROM AUTHOR]

Carbon aerogels represent a distinctive category of high surface area materials derived from sol-gel chemistry. Functionalizing these aerogels has led to the development of composite aerogels with the potential for a wider range of applications. In this study, the technique of lyophilization was employed to fabricate aerogel composites consisting of inorganic salts and cellulosic fibers. Cellulose carbonization can occur through chemical dehydration by heat treatment in an inert atmosphere. X-ray diffraction analysis spectra and scanning electron microscopy images indicate that the formed polymeric composites contain partially carbonized cellulose fibers, amorphous carbon, and calcium carbonates. CaCO3 primarily forms through the reaction of CaCl2, which moistens cellulose or amorphous carbon fibers with CO2 in ammonia fumes. The water loss in 3D structures was analyzed using thermogravimetric analysis, Fourier Transform Infrared Spectroscopy, and ultraviolet-visible-near-infrared spectroscopy. Depending on the synthesis method, 3D structures can be created from partially or completely dehydrated cellulose fibers. The aerogels were examined for their ability to support the growth of bacterial biofilm and then adorned with metal silver and AgCl to produce bactericidal products. Due to their open pores and CaCO3 content, these aerogels can serve as durable and environmentally friendly thermal insulators with bactericidal properties, as well as a medium for absorbing acidic gases.

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel idea of using carbon foam (CF) is introduced to enhance the electrochemical performance of a slurry electrode system in a proton flow reactor system. Steam-activated and acid-washed Norit from peat is used as active charge carrier particles to prepare 15 wt% carbon slurry to be used in this study. The slurry flow rates in the experimental electrochemical system can be varied from 0 to 200 ml min−1, while using two channel widths of 1.6 cm and 2 cm to facilitate the slurry flow. Two sets of CFs with 10 pores per inch (PPI) and 5 PPI are used to understand the effect of introducing CFs with different pore sizes on the performance of slurry electrode. Slurry is charged slurry up to 100 C under constant application of 10 mA and 30 mA. After adding CF, the results show a significant drop in charging potential to generate both levels of current of 25% after using 5 PPI and 41% with 10 PPI. Furthermore, using the narrow channel flow of 1.6 cm and increasing the slurry flow rate from 100 ml min−1 to 150 ml min−1 lower the charging potential considerably by 19% and 21% (compared to base slurry) for 5 PPI and 10 PPI CF, respectively. Application of CF further enables the system to attain higher discharging time during the discharge cycle, and a maximum of 336% and 115% discharging capacity improvement is observed with 10 PPI and 5 PPI CF, respectively. • The use of carbon foam in the context of a slurry-based proton flow reactor is experimentally investigated. • By introducing carbon foam both electronic and ionic resistances of the carbon slurry are reduced significantly. • Slurry charging potential is dropped by 21% and 19% after adding 10 PPI and 5 PPI carbon foams, respectively. [ABSTRACT FROM AUTHOR]

Wood-based N, P co-doped graphene oxide modified foam (N, P-GCF) was prepared by liquefaction, resinization, foaming, carbonization and CO2 activation by liquefaction, resinization, foaming, carbonization and CO2 activation. The surface morphology, crystal structure, chemical properties and hydrophilic properties of N, P-GCF were analyzed by SEM, XRD, Raman, XPS and contact angle measuring instrument, and the effects of N, P-GCF on pore structure, electrochemical properties and capacitance deionization (CDI) were explored by changing the addition amount of NH4H2PO4. The results showed that after GOs modification and NH4H2PO4 doping, the pore size decreases and the disorder increases. N, P-GCF has a hierarchical pore structure. When the doping amount of NH4H2PO4 was 2 g, it had the highest specific surface area of 2684.11 m²/g, total pore volume of 1.42 cm³/g and mesoporosity of 49.45%, and the mass fractions of N and P were 2.48% and 3.46%, respectively. N elements mainly exist in the form of N-5, N-6 and N-X, and P elements are mainly P-C and P-N. Compared with CF, N, P-GCF2.0 has excellent wettability and mechanical properties. In the three-electrode system of 1 mol·L NaCl electrolyte, the specific capacitance of N, P-GCF2.0 is 256.48 F/g at a current density of 1 A/g, and the specific capacitance retention rate is 72.51% when the current density increases to 15 A/g. Under the initial NaCl solution of 500 mg/L and the working voltage of 1.2 V, N, P-GCF2.0 had the best desalination capacity (29.97 mg/g) and salt adsorption rate (1.84 mg/(g·min)), and the retention rate of desalination capacity was 90.12% after 10 cycles, indicating good cycling stability. [ABSTRACT FROM AUTHOR]

Carbon foam is a material with wide application, whereas it is still a challenge whether the catalytic graphitization process of carbon foam can enhance the performance of the final carbon foam material while reducing energy consumption. In this study, a comparative evaluation was performed on the catalytic effects of nickel, iron, and boron catalysts on the graphitization of carbon foam. Subsequently, the influence of different catalyst loading levels and graphitization temperatures on the thermal conductivity of graphitized carbon foam was investigated. The carbon foam materials were analyzed using X-ray Diffraction (XRD) and Raman spectroscopy, while their thermal conductivity properties were characterized using a thermal conductivity meter. The oil yield from the pyrolysis of rich oil shale was also used to evaluate the thermal performance of carbon foam materials. The results revealed that, compared to Fe and Be, Ni was found to be more suitable for graphitization among the tested catalysts. Furthermore, the optimal conditions for achieving the best graphitization effect on carbon foam material were determined to be a nickel nitrate (Ni(NO3)2·6H2O) concentration of 2 mol/L and a graphitization temperature of 1000 °C. The thermal conductivity of the graphitized carbon foam material prepared under this condition was increased by 25.3% from 0.2016 W·m−1·K−1 to 0.2526 W·m−1·K−1, and the tar yield was increased by 46.4% when it was applied to oil-rich coal pyrolysis. This preparation process not only saves energy but also yields graphitized carbon materials with excellent thermal conductivity, holding promising prospects for a wide range of applications. [ABSTRACT FROM AUTHOR]

Carbon aerogels represent a distinctive category of high surface area materials derived from sol-gel chemistry. Functionalizing these aerogels has led to the development of composite aerogels with the potential for a wider range of applications. In this study, the technique of lyophilization was employed to fabricate aerogel composites consisting of inorganic salts and cellulosic fibers. Cellulose carbonization can occur through chemical dehydration by heat treatment in an inert atmosphere. X-ray diffraction analysis spectra and scanning electron microscopy images indicate that the formed polymeric composites contain partially carbonized cellulose fibers, amorphous carbon, and calcium carbonates. CaCO3 primarily forms through the reaction of CaCl2, which moistens cellulose or amorphous carbon fibers with CO2 in ammonia fumes. The water loss in 3D structures was analyzed using thermogravimetric analysis, Fourier Transform Infrared Spectroscopy, and ultraviolet-visible-near-infrared spectroscopy. Depending on the synthesis method, 3D structures can be created from partially or completely dehydrated cellulose fibers. The aerogels were examined for their ability to support the growth of bacterial biofilm and then adorned with metal silver and AgCl to produce bactericidal products. Due to their open pores and CaCO3 content, these aerogels can serve as durable and environmentally friendly thermal insulators with bactericidal properties, as well as a medium for absorbing acidic gases. [ABSTRACT FROM AUTHOR]

Carbon foams with and without functional particles were prepared via a simple direct foaming process. The carbon foams were composed of pyrolytic carbon and graphite. In the foams with additional functional particles, the latter were integrated directly in the direct foaming process. These functional particles were the catalytic material Saponite and the induction heat‐able material MagSilica®. The foams were characterized including the induction heatability. The foams were also successfully tested in an induction heated lab‐scale reactor for a case study reaction, ethanol to 1,3‐butadiene. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the rapid development of science and technology, multifunctional wearable devices have become a major trend in medical field. There is an urgent need to fabricate multifunctional materials with thermal insulation, mechanical flexibility, piezoresistance, and adjustable heating behavior to cope with the thermal management and health monitoring of human body in the harsh environment. To address this issue, three-dimensional melamine-based carbon foams (CMF) have been developed, with sericin-functionalized carbon nanotubes (CNTs) and in situ-grown carbon nanofibers (CNFs) in the CMF skeleton. The strategy of hierarchical porous micro-nanostructure enhanced the synergistic effect between CNTs and CNFs, resulting in exceptional resilience at 0–80 % compressive strain and cyclic stability at 20 % strain. Such carbon foam composites demonstrated excellent piezoresistive sensing performance, wide pressure range (0–20 kPa), high sensitivity (S = 0.11 kPa−1), and quick response (response/recovery time of 150/120 ms). They also showed good thermal insulation and Joule heating properties, particularly in presenting strain-dependent Joule heating mode at low voltage. Such amazing characteristics provide inspiration for temperature regulation of flexible, energy-efficient heating devices, and make them promising for smart sportswear, human-machine interfaces, and wearable medical devices. [ABSTRACT FROM AUTHOR]

Developing materials for efficient energy storage and effective electromagnetic interference (EMI) shielding is crucial in modern technology. This study explores the synthesis and characterization of carbonaceous shape-stabilized octadecane/MWCNT (multi-walled carbon nanotube) composites, utilizing activated carbon, expanded graphite or ceramic carbon foam, as shape stabilizers for phase change materials (PCMs) to enhance thermal energy storage and EMI shielding, for energy-efficient and advanced applications. The integration of octadecane, a phase change material (PCM) with carbonaceous stabilizers ensures the material’s stability during phase transitions, while MWCNTs contribute to improved thermal storage properties and EMI shielding capabilities. The research aims to develop novel composites with dual functionality for thermal storage and EMI shielding, emphasizing the role of carbon matrices and their MWCNT composites. SEM and CT microtomography analyses reveal variations in MWCNT incorporation across the matrices, influenced by surface properties and porosity. Leaching tests, infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) confirm the composite’s stability and high latent heat storage. The presence of nanotubes enhances the thermal properties of octadecane and ΔH values almost reached their theoretical values. EMI shielding effectiveness measurements indicate that the composites show improved electric properties in the presence of MWCNTs.

Multiform NiO nanowalls with a high specific surface area were constructed in situ on carbon foam (CF) to construct NiO@CF/OD composite phase change materials (CPCMs). The synthesis mechanism, microstructures, thermal management capability, and photothermal conversion of NiO@CF/OD CPCMs were systematically studied. Additionally, the collaborative enhancement effects of CF and multiform NiO nanowalls on the thermal properties of OD PCMs were also investigated. NiO@CF not only maintains the porous 3D network structure of CF, but also effectively prevents the aggregation of NiO nanosheets. The chemical structures of NiO@CF/OD CPCMs were analyzed using XRD and FTIR spectroscopy. When combined with CF and NiO nanosheets, OD has high compatibility with NiO@CF. The thermal conductivity of NiO@CF/OD-L CPCMs was 1.12 W/m·K, which is 366.7% higher than that of OD. The improvement in thermal conductivity of CPCMs was theoretically analyzed according to the Debye model. NiO@CF/OD-L CPCMs have a photothermal conversion efficiency up to 77.6%. This article provided a theoretical basis for the optimal design and performance prediction of thermal storage materials and systems.

Melamine-crosslinked polyimide (MPI) aerogels are promising for diverse applications owing to their economical cost and impressive performance. However, MPI aerogels tend to suffer severe shrink in the processes of preparation and practical applications. Their upgrades, i.e., carbon foam-reinforced polyimide (CF-PI) aerogel composites, therefore were proposed in this study, to address this issue. The structure, thermal insulation of the resultant composites as well as their mechanical strength were characterized. The CF-PI aerogel composites were observed to have low shrinkage (as low as 9.25 vol.%) and low thermal conductivity (21 mW m−1 k−1–34 mW m−1 k−1), indicative of significantly improved shape stability and exceptional thermal insulation capability. Besides, these aerogel composites also performed well in thermal stability, and did not decompose unless the temperature exceeds 400 °C. All these advantages contribute to the broad application prospects of thus aerogel composites in many aspects, such as thermal insulation for high temperatures, and so on. Highlights: The carbon foam-reinforced polyimide (CF-PI) aerogel composites have low shrinkage (as low as 9.25 vol.%). The CF-PI aerogel composites have low thermal conductivity (21 mW m−1 k−1–34 mW m−1 k−1). These aerogel composites also performed well in thermal stability, and did not decompose unless the temperature exceeds 400 °C. Since the foam for reinforcement is three-dimensional and can be cut into any shape as desired, the advantages of these CF-PI aerogel composites not only have shape stability, but also can be customized into specific shapes. [ABSTRACT FROM AUTHOR]

[Display omitted] Developing high-efficiency and easy machining components, as well as high-performance energy storage components, is a pressing issue on the road to economic and social progress. Optimizing the interface compatibility between composites and promoting the efficient utilization of the electrochemical active sites are crucial factors in improving the electrochemical performance of composite electrode materials. To address this challenge, a carbon-based flexible lithium-ion supercapacitor positive material (Polyaniline @ Carbon Foam-Supercritical carbon dioxide (P@C-SC)) is synthesized using commercial melamine foam and aniline monomer. The synthesis process utilizes supercritical fluid technology, effectively solving the interface compatibility problem between the composite materials. Consequently, the electrochemical performance of the composite electrode materials is significantly improved. The supercapacitive properties of this material are investigated in 1 mol/L sulfuric acid (H 2 SO 4) and lithium sulfate (Li 2 SO 4) electrolytes using a three-electrode system. In H 2 SO 4 electrolyte, the material exhibits a working voltage of up to 2.2 V and a specific capacitance of 898F/g (at 1 A/g), resulting in a maximum energy density of 50.8 Wh kg−1. Furthermore, this electrode demonstrates superior lithium storage performance, with a specific capacity of approximately 900 mAh/g (at 1 A/g) and a retention of about 400 mAh/g after 200 cycles, along with a coulomb efficiency of 100%. This work offers insights into the integrated design of composite materials with improved electrochemical properties and interface compatibility, thus providing potential applicability of supercritical fluids in the field of lithium-ion supercapacitors. [ABSTRACT FROM AUTHOR]

Electromagnetic pollution could harm sensitive electronic equipment due to the rising use of electronic devices and communication infrastructure. The supercapacitor's electrochemical performance should be enhanced, and electromagnetic damage should be prevented. This study proposes NiCo2O4/CF composites for supercapacitors and microwave absorption. They are made by combining hydrothermal and annealing processes. Dense NiCo2O4 nanoneedles were uniformly grown on the outer layer of carbon foam (CF) as a growth skeleton, preventing the agglomeration of NiCo2O4. The composite had a specific capacitance of 537.5 F/g at 1 A/g. When the current density was set to 1 A/g, the supercapacitor that used NiCo2O4/CF as the cathode had a specific capacitance of 70.7 F/g, and when the current density was increased to 10 A/g, the original specific capacitance of 87.2 % could still be maintained after 5000 charge‐discharge cycles. At a power density of 3695.5 W/kg, an energy density of 22.1 Wh/kg could be maintained. Furthermore, we performed a microwave absorption test and determined its reflection loss curve for various sample thicknesses. Recombination enhanced the composite material's microwave absorption capability by greatly reducing the dielectric loss and the magnetic loss. [ABSTRACT FROM AUTHOR]

Melamine foam (MF), a promising development in light materials, finds application in construction, agriculture, aviation, transportation, electronic message, and other fields due to its excellent thermal insulation performance, sound absorption and noise reduction capabilities, safety and health benefits, as well as easy processing. However, its own shortcomings such as hardness, poor toughness, fragility, and slag removal greatly limit its application scope. In this review, a survey of the literature from two aspects of toughening of melamine resin and regulation of MF pore structure are reviewed to explore the research progress of toughening modification of MF. The principle, merit, and demerit of different modification methods are analyzed. In addition, owing to the extensive literature available, this article also summarizes the representative achievements of the nanotechnology modification of MF derivatives (carbon foam and carbon aerogel). Eventually, based on an assessment of current application status for both MF and its derivatives while considering existing challenges in their modification processes using nanotechnology approaches, we discuss future prospects for their application.

Although pitch-derived carbon foam (CF) is not new, but the progress for enhanced thermal, mechanical, and catalytic dye degradations need to be explored. Numerous works were performed to improve the structural morphology and properties of the CFs by dispersing various additives. But mostly it was noticed that such additives enhanced one aspect of the CFs at the cost of other ones. In this work, various additive loadings of the functionalized graphene oxide (FGO), and functionalized titanium dioxide (FTiO2) were synergistically dispersed into the CF matrix via facile pyrolysis for the preparation of CF/FGO and CF/FGO + FTiO2 hybrid composites to improve the structural morphology and properties of the CFs. Functionalization of the graphene oxide (GO) and titanium dioxide (TiO2) nanoparticles (NPs) was performed for the purpose to decrease the possible aggregations, and enhancing the compatibility and interaction between the additives and the CF matrix. A total of seven CF composites including pure CF were synthesized and explored for their structural, thermal, mechanical, and catalytic dye degradation performances. The microstructural investigations revealed that cellular morphology, pore size, shape, and porous homogeneity of the CF composites were significantly improved after the FGO and FTiO2 loadings. The thermal and mechanical behaviors revealed that as the additives loading of the FGO and FTiO2 are increased, the thermal and mechanical responses of the CF composites are significantly improved. The maximum thermal conductivity of 27.9 W/m K was revealed by 4wt.% CF/FGO + FTiO2 hybrid composite. Similarly, the optimum compressive strength of 15.7 MPa, specific compressive strength of 3.5 10 m3, excellent stress–strain, and improved Young's modulus of 42.2 MPa was shown by 4wt.% FGO + FTiO2 hybrid composite. The catalytic activity was evaluated by degrading orange II dye in an aqueous medium under ultraviolet (UV) light irradiation. The TiO2-containing composite was found to be active and the sample with 4wt.% CF/FGO + FTiO2 hybrid composite achieved a significant 78.9% degradation of the dye within just 80 min.

The preparation of high performance, low cost and recyclable adsorbents is very important to cope with the increasingly devastating water pollution. As a typical three-dimensional porous carbon material, carbon foam (CF) is expected to be a highly efficient adsorbent to wipe out organic dyes from wastewater. However, the uneven size distribution, and lack of adsorption sites signified by insufficient foaming process limit its wider application in the environmental field. Here, CF/carbon nanotubes/graphene oxide (CF/CNTs/GO) composites (adsorbents) were prepared by press-assisted foaming and carbonization methods using mesophase precursors of coal tar pitch and CNTs followed by impregnation of GO nanosheets. The results highlighted that the addition of CNTs facilitated improvement in pore distribution, porosities, and mechanical properties (20 MPa). After treating with GO nanosheets, the adsorption performances of CF/CNTs/GO adsorbents substantially improved due to the increased active sites in the CF/CNTs and the adsorption rate and capacity of methylene blue (MB) reached 73.1% and 146 mg/g respectively. Further, adsorption isotherms (Langmuir and Freundlich), thermodynamics, quasi-first order and quasi-second order kinetics and intraparticle diffusion models were employed to investigate the adsorption mechanism. This work provides a low-cost fabrication technique for the high-performance CF/CNTs/GO adsorbent and is expected to provide reference for application in the treatment of contaminated water. [ABSTRACT FROM AUTHOR]

The presence of dyes in effluents from textile industries has a detrimental effect on aquatic ecosystems as it hinders the process of photosynthesis by reducing the penetration of sunlight. The adsorption capacity of a carbon foam-based iron oxide sorbent obtained from natural sources for the removal of organic methylene blue (MB) dye from water was investigated. The adsorption capacities were examined by batch experiments, wherein the impacts of varying iron content, sorbent dosage, contact time, dye concentration, and characterization were assessed. The physical characteristics and surface morphology of the synthesized carbon foam were also investigated. The carbon precursor and iron oxide precursor were coalesced within a singular container and subjected to carbonization process. This resulted in the formation of a porous structure that is capable of effectively providing support to the iron oxide particles. The carbon foam produced is a self-assembled formation that possesses the characteristic shape and underlying network structure reminiscent of bread. As the number of nanoparticles went up, so did the number of active sites. At elevated temperatures, the interactions between the dye molecules were enhanced, resulting in a more efficient process of dye removal. The magnetite sample exhibited endothermic adsorption, and all other samples exhibited exothermic adsorption. The adsorption of MB onto iron supported by carbon foam did not exhibit intraparticle diffusion as the only rate-limiting step for all samples. The adsorption rate was governed by a multistep elementary reaction mechanism in which multiple processes occurred simultaneously. The experimental data in this study may be accurately modeled by the pseudo-second-order kinetic model (R2 > 0.96). Additionally, the Freundlich isotherm best describes the adsorption equilibrium, which is supported by the outstanding fit of data to the model (R2 > 0.999). The findings suggest that the utilization of a natural carbon foam as a support for an immobilized iron oxide sorbent demonstrates considerable effectiveness in the removal of methylene dye from industrial effluent. [ABSTRACT FROM AUTHOR]

Carbon foam composites, reinforced by micro-nano multiscale phases, were prepared with CNTs modified phenolic resin as the carbon source, magnesium borate whiskers (Mg2B2O5w) and ZrO2 nano-particles as the reinforcement, and hollow microspheres as dispersed phase, respectively. The effects of micro-nano multi-scale phases on the microstructure, mechanical properties, electromagnetic shielding and thermal oxidation properties of the carbon foams were investigated. The results demonstrated that Mg2B2O5w and ZrO2 nano particles contributed a lot to the performance of carbon foam composites synergistically. With the increase of Mg2B2O5w doping, the mechanical properties of the composites first increased and then decreased. The compressive strength reached the maximum (15.4 MPa) with the doping amount of 6 %, which was 111% higher than that of pure carbon foam. Its electromagnetic shielding performance also improved with the increase of Mg2B2O5w doping. The total electromagnetic shielding of 8% CPF was up to 51 dB at 9 GHz, which was 62% higher than that of pure carbon foam. 6% CPF showed the best high-temperature oxidation resistance. Its mass loss reduced from 25% to 15% during isothermal oxidation, at 600 °C for 20 min. The high-temperature oxida¬tion resistance improved by 40 %, compared to that of pure carbon foam. [ABSTRACT FROM AUTHOR]

Creating porous structures and gradient structures are two commonly used design strategies for terahertz (THz) absorption enhancement. However, the synergistic effect of porous structure and gradient structure on THz absorption still remains less explored. Here, we took an almost non-conductive porous carbon foam as raw material, and fabricated an integrated gradient porous carbon foam (PCF) by microwave selective sintering. The experimental results show that the synergistic effect of the porous and gradient structures resulted in a 140% improvement in THz absorption performance. Specifically, an excellent average absorption intensity of −38.8 dB (absorptivity is about 99.99%) is obtained in the frequency range from 0.5 to 4.0 THz. COMSOL simulation and transmission line model were applied to explore the formation mechanism and the gradient loss capabilities of gradient structure. This work not only reveals the synergistic enhancement mechanism of porous and gradient structures for the THz absorption, but also provides new insights into the design of high-performance THz absorbers in the future.

Carbon foam (CF), a lightweight, open-pore, and 3 D interconnected network-like structure comprising turbostratic carbon, is mainly synthesized from polymer precursors like polyurethane and melamine foams, mesophase pitch, coal tar pitch, etc. The glassy variant of CF known as reticulated vitreous carbon (RVC) foam finds use as electrodes in electrochemical cells and Li-ion batteries, field emission cathode, high-temperature insulation, and electromagnetic interference shielding materials. However, of late, its implication has been extended to biomaterial platforms and tissue engineering avenues due to its high porosity and biocompatibility. RVC foam with tunable porosity, density, and mechanical properties can be synthesized by judiciously selecting the precursor materials and their processing conditions. Although proven to be bioinert, its surface modification renders it bioactive and hydrophilic to support cell adhesion and growth. Several groups including ours have demonstrated its implication in supporting osteogenic differentiation of mesenchymal stem cells (MSCs). In this regard, the present review attempts to provide some critical insights into the fabrication, structure, and characteristics of RVC foam and also highlights the challenges and future prospects of this material concerning its plausible implications in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Catalytic activity of a palladium catalyst with a porous carbon support was prepared and tested for benzophenone hydrogenation. The selectivity and yields toward the two possible reaction products (benzhydrol and diphenylmethane) can be directed by the applied solvent. It was found that in isopropanol, the prepared support was selective towards diphenylmethane with high conversion (99% selectivity and 99% benzophenone conversion on 323 K after 240 min). This selectivity might be explained by the presence of the incorporated structural nitrogens in the support. [ABSTRACT FROM AUTHOR]

This research is a follow-up to our recent discovery of a facile strategy for directly converting lignin powder into carbon foam. In this work, we report that the thermal pretreatment parameters in air can remarkably influence the formation and properties of the derived carbon foam. Thermal pretreatment parameters (heating rate, temperature, and residence time) were systematically investigated and a conversion mechanism into carbon foam was proposed. During the thermal pretreatment, relatively low temperatures, low heating rates, and short residence time hindered the formation of smooth and well-connected structures in the carbon foam. The overall product yields were similar regardless of the thermal pretreatment conditions. The densities of the different carbon foams ranged 0.27–0.83 g·cm−3. The carbon foams with the highest compressive strengths (> 10 MPa) were KLPC280-2-5, KLPC300-0-5, and KLPC300-2-2.5. KLPC280-2-5 exhibited a high iodine sorption value (182 mg·g−1). KLPC300-2-5 exhibited a specific capacitance of 158 F·g−1 at a current density of 0.05 A·g−1. The maximum evaporation rates in the solar vapor generation experiments were 1.05 and 1.38 kg·m−2·h−1 under 100 and 150 mW·cm−2 irradiation, respectively. The good performances are attributed to the robust, porous, and continuous structure. [ABSTRACT FROM AUTHOR]

Multifunctional microwave absorbing materials with properties of high absorbing performance, infrared stealth, thermal insulation are urgently required to cope with current complex and extreme electromagnetic environment. To solve this problem, a three-dimensional carbon foam (CF) was used as a matrix, and Fe/C nanocubes derived from Prussian Blue (PB) were uniformly distributed throughout the CF skeleton. Such design of Fe/C/CF porous structures enhanced the synergistic effects between dielectric and magnetic loss to reach a better absorbing performance. The minimum reflection loss (RL) of hybrid foam is −66.7 dB, and the widest effective absorbing bandwidth (EAB, RL < −10dB) is 6.34 GHz. Moreover, the hybrid foam showed remarkable infrared stealth and thermal insulation properties. The surface temperature of hybrid foam almost unchanged while it was heated under 100 °C for more than 1 h. It is noteworthy that the preparation process of hybrid foam was a facile, recycled, and low-cost strategy for achieving high-performance absorbing materials. Besides, the mentioned methods may provide inspirations for the preparation of high-performance microwave absorbing materials and increase the potential application fields in complex actual scenarios. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Basic Sciences Journal of Textile Universities / Fangzhi Gaoxiao Jichu Kexue Xuebao is the property of Basic Sciences Journal of Textile Universities and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluates the possibilities to produce new materials, starting from Moroccan oil shales, for different applications. More specifically, the authors aimed to demonstrate that the organic fraction of the oil shales could be used as a precursor of carbon foams and graphitizable carbons, after appropriate chemical treatments resulting in the âmaturationâ of this organic phase. First, the researchers studied the optimization of experimental conditions and the identification of various parameters influencing the yield and composition of oils obtained by the supercritical extraction of Moroccan oil shale. The effect of various experimental parameters, such as mineral matter, thermal treatment temperature (T), treatment duration (t) and solvent type, was studied. The experimental results obtained show clearly that the organic matter contained in the Moroccan Tarfaya oil shale (sub-layer R3 ) can be recovered by phenol under the following optimal conditions: T = 390 °C, t = 2.5 hours using phenol as a solvent with an amount of 15 g for each 10 g of sub-layer R3 carbonate-free oil shale (RH). The results reveal that the yield and composition of the oil obtained by extraction with phenol is markedly different from those obtained by extraction with toluene, quinoline or without solvent. Furthermore, the phenol has a very signiï¬cant role in increasing the recovery yield and the degree of maturation of the obtained oil. It was shown that phenol was a suitable extraction solvent to produce graphitizable carbon at a relatively low temperature, below 1800 °C.

Carbon foam catalysts (CF1, CF2, CF3) were prepared by spontaneous foaming method using Liulin coal (LL) as raw materials, and the pyrolysis experiments of Xinjiang Naomaohu long-flame coal (NMH) and Inner Mongolia Shengli lignite coal (SL) were performed by Py-GC/MS at 700 ℃. The effects of carbon foam catalysts with different pore structure on the distribution of gaseous tar products were investigated. The results show that compared with normal semicoke catalyst (SC), carbon foam catalysts have more significant advantages in improving the quality of tar from coal pyrolysis. The catalytic performance of carbon foam catalysts is closely related to its pore structure and chemical character. After the action of CF1, the total amount of tar during pyrolysis of NMH and SL is significantly increased (the increase rates are 10.26% and 31.31%, respectively), which is related to its suitable specific surface area (281.14 m2/g), rich micropore structure (microporous area accounts for 88.96% of the total specific surface area), and appropriate reactivity. CF2 and CF3 with rich hierarchical pore structure and higher reactivity make the total amount of NMH and SL tar decrease. In addition, the relative content of light aromatic hydrocarbons in gaseous tar of coal pyrolysis increases and the relative content of compounds containing O, N and S decreases by CF catalysts. These results indicate that these CF catalysts can significantly promote catalytic cracking, deoxidation, aromatization, and other reactions during the pyrolysis of NMH and SL, and can directionally control the distribution of gaseous tar from coal pyrolysis.

Phase Change Materials (PCMs) has gained considerable interest for storing thermal energy originating from the solar irradiation, industrial waste heat and surplus heat. Here, we present the facile and scalable synthesis of PCM-carbon foam composites by using polyisocyanurate (PIR) foam derived carbon foam as porous support. The unique 3D molecular configuration of the carbon foam materials embedded the composites with high PCM loading capacity, excellent shape stabilization and thermal reliability and chemical stability. The carbon foams prepared by facile chemical activation method with high surface area up to 1968 m2/g exhibit high PCM loading capacity of up to 90.8 wt% and excellent energy storage capacity of up to 105.2 J/g. Advanced characterization demonstrated that the total pore volume of carbon foam governs the PCM loading capacity as well as the energy storage performance of the composites. This work provides a potential pathway to recycle PIR foams, which have been widely used in construction industry, by producing cost-effective PCM composites for thermal energy storage.

Defect engineering exerts a crucial impact on polarization loss and thereby enhances electromagnetic (EM) wave absorption ability. The EM loss mechanism beneath of morphology conversion is usually vaguely considered as the synergism of multiple mechanisms. Morphology induced defects and its dominated polarization loss mechanisms are little focus on. In this work, MnO 2 /Carbon foam (MCF) composites with tunable morphology were prepared via facile hydrothermal and annealing process. Morphological conversion of MnO 2 and its induced defects were achieved by KMnO 4 concentration, which contributes to the reduction of conductive loss, optimization of impedance matching, increase of polarization loss and multiple scattering. Therefore, the minimum reflection loss of MCF composite harvests −65.18 dB at 3.19 mm and the broad effective absorption bandwidth covers the entire X band. Despite multiple dissipation mechanisms, the excellent performance is dominated by morphology modulated defects in MCF composites. Besides, the optimal MCF composite displays a high compressive strength of 14.647 MPa. According to the results of computer simulation technology, the MCF composite can attenuate EM energy in the actual condition. This work is expected to offer an inspired understanding of morphology modulated defects toward high-performance of EM wave absorption materials. [Display omitted] • MnO 2 /CF with diversed morphologies and defects were rely on the content of KMnO 4. • Morphological evolution changed carbon defect, oxygen vacancy and lattice defects. • Effective absorption bandwidth of 4.2 GHz and reflection loss of −65.18 dB were achieved. • Defect deduced polarization loss can effectively enhance MA performance. • The RCS contribution of MnO 2 /CF composites in far field was calculated by CST. [ABSTRACT FROM AUTHOR]

This work presents the results of a tribological examination of polymer matrix composites reinforced with carbon foams with different porosity. The application of open-celled carbon foams allows an easy infiltration process by liquid epoxy resin. At the same time, carbon reinforcement remains its initial structure, which prevents its segregation in polymer matrix. Dry friction tests, conducted under 0.7, 2.1, 3.5 and 5.0 MPa loads, show that higher friction load results in higher mass loss, but it strongly lowers the coefficient of friction (COF). The change in coefficient of friction is related to the size of the pores of the carbon foam. Open-celled foams with pores size below 0.6 mm (40 and 60 ppi), used as a reinforcement in epoxy matrix, allow to obtain COF twice lower than composite reinforced with 20 ppi open-celled foam. This phenomenon occurs due to a change of friction mechanisms. In composites reinforced with open-celled foams, general wear mechanism is related to destruction of carbon components, which results in solid tribofilm formation. The application of novel reinforcement, in the form of open-celled foams with stable distance between carbon components, allows the decrease of COF and the improvement of stability, even under a very high friction load. [ABSTRACT FROM AUTHOR]

For electromagnetic wave-absorbing materials, maximizing absorption at a specific frequency has been constantly achieved, but enhancing the absorption properties in the entire band remains a challenge. In this work, a 3D porous pyrolytic carbon (PyC) foam matrix was synthesized by a template method. Amorphous carbon nanotubes (CNTs) were then in-situ grown on the matrix surface to obtain ultralight CNTs/PyC foam. These in-situ grown amorphous CNTs were distributed uniformly and controlled by the catalytic growth time and can enhance the interface polarization and conduction loss of composites. When the electromagnetic wave enters the internal holes, the electromagnetic energy can be completely attenuated under the combined action of polarization, conductivity loss, and multiple reflections. The ultralight CNTs/PyC foam had a density of 22.0 mg·cm−3 and a reflection coefficient lower than −13.3 dB in the whole X-band (8.2–12.4 GHz), which is better than the conventional standard of effective absorption bandwidth (≤−10 dB). The results provide ideas for researching ultralight and strong electromagnetic wave absorbing materials in the X-band. [ABSTRACT FROM AUTHOR]

Aqueous Zn-ion batteries (AZIBs) are one of the most promising large-scale energy storage devices due to the excellent characteristics of zinc metal anode, including high theoretical capacity, high safety and low cost. Nevertheless, the large-scale applications of AZIBs are mainly limited by uncontrollable Zn deposition and notorious Zn dendritic growth, resulting in low plating/stripping coulombic efficiency and unsatisfactory cyclic stability. To address these issues, herein, a carbon foam (CF) was fabricated via melamine-foam carbonization as a scaffold for a dendrite-free and stable Zn anode. Results showed that the abundant zincophilicity functional groups and conductive three-dimensional network of this carbon foam could effectively regulate Zn deposition and alleviate the Zn anode's volume expansion during cycling. Consequently, the symmetric cell with CF@Zn electrode exhibited lower voltage hysteresis (32.4 mV) and longer cycling performance (750 h) than the pure Zn symmetric cell at 1 mA cm−2 and 1 mAh cm−2. Furthermore, the full battery coupling CF@Zn anode with MnO2 cathode can exhibit a higher initial capacity and better cyclic performance than the one with the bare Zn anode. This work brings a new idea for the design of three-dimensional (3D) current collectors for stable zinc metal anode toward high-performance AZIBs. [ABSTRACT FROM AUTHOR]

The potential use of magnetic nanopowder for phenol adsorption mobilised on natural grain carbon foam from an aqueous solution was studied. Phenolic compounds are priority pollutants with high toxicity even at low concentrations. A magnetic nanopowder was synthesised by dissolving an iron sponge in nitric acid to produce iron nitrate, which was added to a natural grain mixture with flour as the main ingredient. The synthesised carbon foam was investigated for the effects of initial concentration, time, and TEM (transmission electron microscopy) characterisation. The phenol adsorption increased as the iron content of the carbon foam and the initial concentration increased. A kinetic study showed that the phenol adsorption data adequately covered all the carbon foam samples tested using an equation corresponding to a pseudo-first order chemical reaction. The Freundlich, Langmuir, and Temkin equations were tested for modelling the adsorption isotherms at equilibrium, and it was concluded that the Temkin model fit the experimental data adequately. Due to its exceptional physical and chemical properties, carbon magnetic nanopowder is regarded as an outstanding pollutant absorber in environmental investigations. R2 values derived from the pseudo-first-order model exceed 0.99. R2 > 0.94 indicates that the Freundlich isotherm provides the best fit to the equilibrium data. [ABSTRACT FROM AUTHOR]

Efforts in a large number of transition metal-carbon systems are devoted to the development of efficient catalysts for oxygen reduction reaction (ORR). However, unsatisfied O2 adsorption and slow reduction of OH* at the active centers hinder the further development of these catalysts. We here report a gasifiable reductant strategy, of which a new Cu-based metal organic framework (MOF: termed NTU-83) nanosheet was co-pyrolyzed with melamine to produce the N-coordinated atomic Cu and multi-oxidated Cu2+1O active centers on the carbon foam with ultrathin skeleton. The engineered electrons and configuration of the active centers boost the catalyst (Cu/NC-1000) to show superior ORR activity (E1/2 = 0.85 V), excellent stability, and methanol resistance. Further modeling calculation and controlled experiments reveal that the Cu2+1O species play a crucial role in kinetically accelerated adsorption and activation of O2, while the N4 coordinated atomic Cu facilitates fast reduction of OH*. Such characteristics endow the Zn-air battery that containing Cu/NC-1000 as air cathode to show a high peak power density (138 mW·cm−2), a high specific capacity of 763 mAh·gZn−1, and outstanding long-term cycle stability. The plausible mechanism and excellent performance show that gasifiable reductant strategy opens up a new route for regulation of the electronic of active sites but also provides a candidate for the practical application in energy conversion/storage devices. [ABSTRACT FROM AUTHOR]

Copyright of Basic Sciences Journal of Textile Universities / Fangzhi Gaoxiao Jichu Kexue Xuebao is the property of Basic Sciences Journal of Textile Universities and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The drawbacks of single loss capability and skin effect severely impede the electromagnetic (EM) wave absorption performance of carbon-based materials. Developing a rational hierarchical structure with high efficiency and facile method to optimize impedance matching and improve EM wave absorption performance still remains challenge. Herein, SiC nws /carbon foam (SCF) composites with hierarchical structure, were successfully prepared by chemical vapor deposition method. The core shell structure of SiC nws @SiO 2 was grown on the scaffold and inside of the cell structure in CFs. Significantly, the amount of SiC nws can be modulated by the growth temperature. Benefiting from the impedance gradient structure, coupled with interface polarization dominated loss mechanism jointly promoted the excellent EM wave absorption performance. Specifically, when the growth temperature is 1400 °C, the SCF composite achieved an optimal reflection loss value of −55.8 dB at 10.30 GHz with a thickness of 4.35 mm and a wide effective absorption bandwidth of 3.97 GHz at 3.71 mm. Meanwhile, in-situ growth of SiC nws in CFs substantially increased the compressive strength to 21.08 MPa. This work paves a new avenue to develop highly efficient EM wave absorption materials with hierarchical structures. [Display omitted] • The hierarchical core-shell SiC nws @SiO 2 -carbon foam hybrid composites were prepared by a facile CVD method. • SiC nws in-situ grown in CFs endowed composites well impedance matching. • The EAB of 3.97 GHz and RL min of −55.80 dB were achieved. • The enhanced EM wave absorption mechanisms were investigated in detail. [ABSTRACT FROM AUTHOR]

A three-dimensional porous carbon foam absorber was prepared by surfactant foaming method. The relative content of organic matter/C for carbon foam was adjusted by varying the carbonization temperature. The relationship of organic matter/C, light absorption and thermal conductivity was studied to find an optimal equilibrium for comprehensively optimizing the solar steam evaporation performance. Results show that the carbonization temperature has a great effect on the relative content of organic matter/C and pore structure of carbon foam. With reducing relative content of organic matter/C, it demonstrates a significant improvement for light absorption, but also suffers a decrease of thermal insulation performance, which worsens the thermal management ability of solar evaporation system. When carbonized at 600 ℃, the carbon foam absorber can acquire a optimal equilibrium between light absorption and thermal management, which reveals the highest absorption rate (96.5%) and best solar steam evaporation performance (1.0391 kg/ (m²·h)). The vapor evaporation rate is 2.08 times higher than that of pure water. [ABSTRACT FROM AUTHOR]

This study evaluates the possibilities to produce new materials, starting from Moroccan oil shales, for different applications. More specifically, the authors aimed to demonstrate that the organic fraction of the oil shales could be used as a precursor of carbon foams and graphitizable carbons, after appropriate chemical treatments resulting in the “maturation” of this organic phase. First, the researchers studied the optimization of experimental conditions and the identification of various parameters influencing the yield and composition of oils obtained by the supercritical extraction of Moroccan oil shale. The effect of various experimental parameters, such as mineral matter, thermal treatment temperature (T), treatment duration (t) and solvent type, was studied. The experimental results obtained show clearly that the organic matter contained in the Moroccan Tarfaya oil shale (sub-layer R3 ) can be recovered by phenol under the following optimal conditions: T = 390 °C, t = 2.5 hours using phenol as a solvent with an amount of 15 g for each 10 g of sub-layer R3 carbonate-free oil shale (RH). The results reveal that the yield and composition of the oil obtained by extraction with phenol is markedly different from those obtained by extraction with toluene, quinoline or withoutsolvent. Furthermore, the phenol has a very significant role in increasing the recovery yield and the degree of maturation of the obtained oil. It was shown that phenol was a suitable extraction solvent to produce graphitizable carbon at a relatively low temperature, below 1800 °C. [ABSTRACT FROM AUTHOR]

Carbon foam, an extremely attractive new material type for important fields of application, with low density (0.28 g cm-3 ), low thermal conductivity (0.110 W m-1 K-1 ), relatively high compressive strength (3.5 MPa), high electrical conductivity (29.8 S m-1 ), and very high electromagnetic shielding effectiveness (46 dB) was experimentally made using recycled wood biomass from industrial wood processing and aqueous solution of sucrose. The carbonization was performed by heating at 750 ºC through microwave irradiation technique, the pressed and dried material in the intermediate state being introduced into a SiC crucible with a lid, thermally protected with ceramic fiber, without inert medium. The specific energy consumption was very low (0.785 kWh/kg), unlike the high energy consumption of the usually carbonization stages. The optimal carbon foam specimen was considered suitable for the special application fields (military, aeronautics, construction, transport). [ABSTRACT FROM AUTHOR]

Copyright of Basic Sciences Journal of Textile Universities / Fangzhi Gaoxiao Jichu Kexue Xuebao is the property of Basic Sciences Journal of Textile Universities and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)