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Extrusion 3D printing of carbon nanotube-assembled carbon aerogel nanocomposites with high electrical conductivity
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作者 Lukai Wang Jing Men +4 位作者 Junzong Feng Yonggang Jiang Liangjun Li Yijie Hu Jian Feng 《Nano Materials Science》 EI CAS CSCD 2024年第3期312-319,共8页
Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shapi... Carbon nanotubes(CNTs)with high aspect ratio and excellent electrical conduction offer huge functional improvements for current carbon aerogels.However,there remains a major challenge for achieving the on-demand shaping of carbon aerogels with tailored micro-nano structural textures and geometric features.Herein,a facile extrusion 3D printing strategy has been proposed for fabricating CNT-assembled carbon(CNT/C)aerogel nanocomposites through the extrusion printing of pseudoplastic carbomer-based inks,in which the stable dispersion of CNT nanofibers has been achieved relying on the high viscosity of carbomer microgels.After extrusion printing,the chemical solidification through polymerizing RF sols enables 3D-printed aerogel nanocomposites to display high shape fidelity in macroscopic geometries.Benefiting from the micro-nano scale assembly of CNT nanofiber networks and carbon nanoparticle networks in composite phases,3D-printed CNT/C aerogels exhibit enhanced mechanical strength(fracture strength,0.79 MPa)and typical porous structure characteristics,including low density(0.220 g cm^(-3)),high surface area(298.4 m^(2)g^(-1)),and concentrated pore diameter distribution(~32.8nm).More importantly,CNT nanofibers provide an efficient electron transport pathway,imparting 3D-printed CNT/C aerogel composites with a high electrical conductivity of 1.49 S cm^(-1).Our work would offer feasible guidelines for the design and fabrication of shape-dominated functional materials by additive manufacturing. 展开更多
关键词 carbon aerogel Extrusion 3D printing carbon nanotube Electrical conductivity RHEOLOGY
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In Situ Mineralization of Biomass-Derived Hydrogels Boosts Capacitive Electrochemical Energy Storage in Free-Standing 3D Carbon Aerogels
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作者 Anjali Achazhiyath Edathil Babak Rezaei +1 位作者 Kristoffer Almdal Stephan Sylνest Keller 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期359-371,共13页
Here,a novel fabrication method for making free-standing 3D hierarchical porous carbon aerogels from molecularly engineered biomass-derived hydrogels is presented.In situ formed flower-like CaCO_(3)molecularly embedde... Here,a novel fabrication method for making free-standing 3D hierarchical porous carbon aerogels from molecularly engineered biomass-derived hydrogels is presented.In situ formed flower-like CaCO_(3)molecularly embedded within the hydrogel network regulated the pore structure during in situ mineralization assisted one-step activation graphitization(iMAG),while the intrinsic structural integrity of the carbon aerogels was maintained.The homogenously distributed minerals simultaneously acted as a hard template,activating agent,and graphitization catalyst.The decomposition of the homogenously distributed CaCO_(3)during iMAG followed by the etching of residual CaO through a mild acid washing endowed a robust carbon aerogel with high porosity and excellent electrochemical performance.At 0.5 mA cm^(-2),the gravimetric capacitance increased from 0.01 F g^(-1)without mineralization to 322 F g^(-1)with iMAG,which exceeds values reported for any other free-standing or powder-based biomass-derived carbon electrodes.An outstanding cycling stability of~104%after 1000 cycles in 1 M HClO4 was demonstrated.The assembled symmetric supercapacitor device delivered a high specific capacitance of 376 F g^(-1)and a high energy density of 26 W h kg^(-1)at a power density of 4000 W kg^(-1),with excellent cycling performance(98.5%retention after 2000 cycles).In combination with the proposed 3D printed mold-assisted solution casting(3DMASC),iMAG allows for the generation of free-standing carbon aerogel architectures with arbitrary shapes.Furthermore,the novel method introduces flexibility in constructing free-standing carbon aerogels from any ionically cross-linkable biopolymer while maintaining the ability to tailor the design,dimensions,and pore size distribution for specific energy storage applications. 展开更多
关键词 BIOMASS carbon aerogel sustainable energy materials FREE-STANDING SUPERcaPACITORS
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Heteroatom tuning in agarose derived carbon aerogel for enhanced potassium ion multiple energy storage
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作者 Kaijun Xie Xin Liu +5 位作者 Haolin Li Long Fang Kai Xia Dongjiang Yang Yihui Zou Xiaodong Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期239-254,共16页
The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of... The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure carbon.However,the evolution of the electronic structure from single-atom doping to heteroatom codoping in CAs has not yet been thoroughly investigated,and the impact of codoping on potassium ion(K+)storage and diffusion pathways as electrode material remains unclear.In this study,experimental and theoretical simulations were conducted to demonstrate that heteroatom codoping,composed of multiple heteroatoms(O/N/B)with different properties,has the potential to improve the electrical properties and stability of CAs compared to single-atom doping.Electronic states near the Fermi level have revealed that doping with O/N/B generates a greater number of active centers on adjacent carbon atoms than doping with O and O/N atoms.As a result of synergy with enhanced wetting ability(contact angle of 9.26°)derived from amino groups and hierarchical porous structure,ON-CA has the most optimized adsorption capacity(−1.62 eV)and diffusion barrier(0.12 eV)of K^(+).The optimal pathway of K^(+)in ON-CA is along the carbon ring with N or O doping.As K^(+)storage material for supercapacitors and ion batteries,it shows an outstanding specific capacity and capacitance,electrochemical stability,and rate performance.Especially,the assembled symmetrical K^(+)supercapacitor demonstrates an energy density of 51.8 Wh kg^(−1),an ultrahigh power density of 443Wkg^(−1),and outstanding cycling stability(maintaining 83.3%after 10,000 cycles in 1M KPF6 organic electrolyte).This research provides valuable insights into the design of highperformance potassium ion storage materials. 展开更多
关键词 AGAROSE carbon aerogels O/N/B codoping potassium-ion battery potassium-ion supercapacitor
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Biomass Homogeneity Reinforced Carbon Aerogels Derived Functional Phase-Change Materials for Solar–Thermal Energy Conversion and Storage 被引量:3
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作者 Qingfeng Zhang Tingfeng Xia +12 位作者 Qihan Zhang Yucao Zhu Huanzhi Zhang Fen Xu Lixian Sun Xiaodong Wang Yongpeng Xia Xiangcheng Lin Hongliang Peng Pengru Huang Yongjin Zou Hailiang Chu Bin Li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期164-176,共13页
We deviseda functional form stable compositephase-change materials(PCMs)toachieve a three-dimensional(3D)interconnectedporous carbon aerogel structure for encapsulating polyethyleneglycol(PEG).Anovelhomogeneity reinfo... We deviseda functional form stable compositephase-change materials(PCMs)toachieve a three-dimensional(3D)interconnectedporous carbon aerogel structure for encapsulating polyethyleneglycol(PEG).Anovelhomogeneity reinforced carbonaerogel witha well-interconnected porous structure was constructed bycombining a flexible carbonresource from biomass guar gum with hard-brittle carbonfrom polyimide,to overcome severeshrinkage andpoor mechanical performance of traditionalcarbon aerogel.Thesupportingcarbon aerogel-encapsulated PEG produced thenovel composite PCMswithgood structure stability andcomprehensive energy storage performance.Theresults showed thatthecomposite PCMsdisplayed awell-defined 3Dinterconnected structure,and theirenergy storage capacities were 171.5 and169.5 J/g,which changed onlyslightlyafter 100 thermalcycles,andthe compositescould maintainthe equilibrium temperature at50.0−58.1℃ for about 760.3 s.The thermal conductivityofthe compositescould reach0.62 W m^(−1) K^(−1),which effectively enhanced the thermalresponse rate.And thecomposite PCMs exhibited good leakage-proof performance andexcellent light–thermal conversion.The compressive strengthof thecomposite PCMscan improveupto 1.602 MPa.Results indicatethatthisstrategy canbe efficiently usedtodevelop novel composite PCMswithimproved comprehensive thermalperformance and high light–thermal conversion. 展开更多
关键词 carbon aerogels composite PCMs energy storage capacity solar-thermal conversion
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Three-Dimensional N-Doped Carbon Nanotube/Graphene Composite Aerogel Anode to Develop High-Power Microbial Fuel Cell 被引量:1
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作者 Shixuan Jin Yiyu Feng +10 位作者 Jichao Jia Fulai Zhao Zijie Wu Peng Long Feng Li Huitao Yu Chi Yang Qijing Liu Baocai Zhang Hao Song Wei Feng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期161-169,共9页
Optimizing the structure of electrode materials is one of the most effective strategies for designing high-power microbial fuel cells(MFCs).However,electrode materials currently suffer from a series of shortcomings th... Optimizing the structure of electrode materials is one of the most effective strategies for designing high-power microbial fuel cells(MFCs).However,electrode materials currently suffer from a series of shortcomings that limit the output of MFCs,such as high intrinsic resistance,poor electrolyte wettability,and low microbial load capacity.Here,a three-dimensional(3D)nitrogen-doped multiwalled carbon nanotube/graphene(N-MWCNT/GA)composite aerogel is synthesized as the anode for MFCs.Comparing nitrogen-doped GA,MWCNT/GA,and N-MWCNT/GA,the macroporous hydrophilic N-MWCNT/GA electrode with an average pore size of 4.24μm enables high-density loading of the microbes and facilitates extracellular electron transfer with low intrinsic resistance.Consequently,the hydrophilic surface of N-MWCNT can generate high charge mobility,enabling a high-power output performance of the MFC.In consequence,the MFC system based on N-MWCNT/GA anode exhibits a peak power density and output voltage of 2977.8 mW m^(−2)and 0.654 V,which are 1.83 times and 16.3%higher than those obtained with MWCNT/GA,respectively.These results demonstrate that 3D N-MWCNT/GA anodes can be developed for high-power MFCs in different environments by optimizing their chemical and microstructures. 展开更多
关键词 ANODE graphene aerogel microbial fuel cell N-doped carbon nanotube
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Cellulose nanofiber-derived carbon aerogel for advanced room-temperature sodium–sulfur batteries 被引量:1
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作者 Wu Yang Wang Yang +4 位作者 Ren Zou Yongfa Huang Haihong Lai Zehong Chen Xinwen Peng 《Carbon Energy》 SCIE CAS CSCD 2023年第1期1-15,共15页
Room-temperature sodium–sulfur(RT/Na–S)batteries are regarded as promising large-scale stationary energy storage systems owing to their high energy density and low cost as well as the earth-abundant reserves of sodi... Room-temperature sodium–sulfur(RT/Na–S)batteries are regarded as promising large-scale stationary energy storage systems owing to their high energy density and low cost as well as the earth-abundant reserves of sodium and sulfur.However,the diffusion of polysulfides and sluggish kinetics of conversion reactions are still major challenges for their application.Herein,we developed a powerful and functional separator to inhibit the shuttle effect by coating a lightweight three-dimensional cellulose nanofiber-derived carbon aerogel on a glass fiber separator(denoted NSCA@GF).The hierarchical porous structures,favorable electronic conductivity,and three-dimensional interconnected network of N,S-codoped carbon aerogel endow a multifunctional separator with strong polysulfide anchoring capability and fast reaction kinetics of polysulfide conversion,which can act as the barrier layer and an expanded current collector to increase sulfur utilization.Moreover,the hetero-doped N/S sites are believed to strengthen polysulfide anchoring capability via chemisorption and accelerate the redox kinetics of polysulfide conversion,which is confirmed from experimental and theoretical results.As a result,the assembled Na–S coin cells with the NSCA@GF separator showed a high reversible capacity(788.8 mAh g^(−1) at 0.1 C after 100 cycles)and superior cycling stability(only 0.059%capacity decay per cycle over 1000 cycles at 1 C),thereby demonstrating the significant potential for application in high-performance RT/Na–S batteries. 展开更多
关键词 carbon aerogel cellulose nanofiber N S codoping redox kinetics sodium–sulfur batteries
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Modulating Pd e_(g) orbital occupancy in Pd-Au metallic aerogels for efficient carbon dioxide reduction
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作者 Yao Chen Juan Wang +8 位作者 Tingjie Mao Cun Chen Hanjun Li Honggang Huang Hui Fu Feili Lai Jiadong Chen Nan Zhang Tianxi Liu 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期98-104,I0004,共8页
The electronic structure of electrocatalysts plays a critical role in energy conversion,whereas for an efficient catalyst,it is challenging to modulate the orbitals.Herein,we present a new strategy to modulate the e_(... The electronic structure of electrocatalysts plays a critical role in energy conversion,whereas for an efficient catalyst,it is challenging to modulate the orbitals.Herein,we present a new strategy to modulate the e_(g) orbital occupancy of Pd by constructing composition-controllable Pd-Au metallic aerogels(MAs),optimizing the d-band center of Pd to achieve excellent performance for electrochemical carbon dioxide reduction reaction(CO_(2)RR).Specifically,Pd_(1)Au_(2) MAs achieve almost 100% Faraday efficiency(FE) of CO in the range of-0.40 to-0.80 V vs.reversible hydrogen electrode(RHE),as well as the long-term stability,being one of the best Pd-based materials for CO_(2)RR.The X-ray photoelectron spectroscopy(XPS) results and density functional theory(DFT) calculations demonstrate that the introduction of Au modulates the Pd e_(g) orbital occupancy,which significantly weakens *CO adsorption on Pd,reduces the CO_(2)RR energy barrier and consequently improves the electrocatalytic activity and stability for long-term applications.Our work highlights a new strategy for designing efficient electrocatalysts for CO_(2)RR and beyond. 展开更多
关键词 PD carbon dioxide reduction Alloy aerogelS Orbital occupancy
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基于InVEST与CA-Markov模型的宝鸡市碳储量时空演变与预测
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作者 刘静 易文利 +2 位作者 刘佳薇 潘照 王珊珊 《河南科学》 2024年第9期1281-1289,共9页
土地利用类型的变化是影响陆地生态系统碳储量变化的重要因素,分析区域未来土地利用格局对碳储量的影响、对维持碳平衡具有重要意义.基于宝鸡市2000—2020年土地利用数据,运用InVEST模型和CA-Markov模型,对2000—2020年宝鸡市不同土地... 土地利用类型的变化是影响陆地生态系统碳储量变化的重要因素,分析区域未来土地利用格局对碳储量的影响、对维持碳平衡具有重要意义.基于宝鸡市2000—2020年土地利用数据,运用InVEST模型和CA-Markov模型,对2000—2020年宝鸡市不同土地利用类型碳储量的变化特征进行分析,并对2030年不同情景下宝鸡市土地利用变化及碳储量变化情况进行了预测.研究表明:①2000—2020年宝鸡市建设用地面积不断增加,耕地、林地和草地为主要土地利用类型.②2000—2020年,宝鸡市碳储量共损失0.42×10^(6)t,耕地和林地面积减少是其碳储量减少的主要原因.③2020—2030年自然发展情景下宝鸡市碳储量损失最多,耕地保护情景和生态保护情景下宝鸡市碳储量相差不大,控制城市扩张情景下宝鸡市碳储量损失最少、固碳能力最强.因此,未来进行国土空间规划时,可统筹考虑控制城市扩张情景、生态保护情景和耕地保护情景,以确保在粮食供给和生态安全的基础上,提高研究区的碳储量. 展开更多
关键词 碳储量 土地利用变化 InVEST模型 ca-Markov模型 宝鸡市
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Lightweight,Flexible Cellulose-Derived Carbon Aerogel@Reduced Graphene Oxide/PDMS Composites with Outstanding EMI Shielding Performances and Excellent Thermal Conductivities 被引量:46
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作者 Ping Song Bei Liu +5 位作者 Chaobo Liang Kunpeng Ruan Hua Qiu Zhonglei Ma Yongqiang Guo Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第6期126-142,共17页
In order to ensure the operational reliability and infor-mation security of sophisticated electronic components and to protect human health,efficient electromagnetic interference(EMI)shielding materials are required t... In order to ensure the operational reliability and infor-mation security of sophisticated electronic components and to protect human health,efficient electromagnetic interference(EMI)shielding materials are required to attenuate electromagnetic wave energy.In this work,the cellulose solution is obtained by dissolving cotton through hydrogen bond driving self-assembly using sodium hydroxide(NaOH)/urea solution,and cellulose aerogels(CA)are prepared by gelation and freeze-drying.Then,the cellulose carbon aerogel@reduced graphene oxide aerogels(CCA@rGO)are prepared by vacuum impregnation,freeze-drying followed by thermal annealing,and finally,the CCA@rGO/polydimethylsiloxane(PDMS)EMI shielding composites are prepared by backfilling with PDMS.Owing to skin-core structure of CCA@rGO,the complete three-dimensional(3D)double-layer con-ductive network can be successfully constructed.When the loading of CCA@rGO is 3.05 wt%,CCA@rGO/PDMS EMI shielding composites have an excellent EMI shielding effectiveness(EMI SE)of 51 dB,which is 3.9 times higher than that of the co-blended CCA/rGO/PDMS EMI shielding composites(13 dB)with the same loading of fillers.At this time,the CCA@rGO/PDMS EMI shielding composites have excellent thermal stability(T_(HRI) of 178.3℃)and good thermal conductivity coefficient(λ of 0.65 W m^(-1) K^(-1)).Excellent comprehensive performance makes CCA@rGO/PDMS EMI shielding composites great prospect for applications in lightweight,flexible EMI shielding composites. 展开更多
关键词 POLYDIMETHYLSILOXANE Electromagnetic interference shielding Cellulose carbon aerogel Reduced graphene oxide
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Environmentally Friendly and Multifunctional Shaddock Peel-Based Carbon Aerogel for Thermal-Insulation and Microwave Absorption 被引量:30
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作者 Weihua Gu Jiaqi Sheng +3 位作者 Qianqian Huang Gehuan Wang Jiabin Chen Guangbin Ji 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第7期28-41,共14页
Eco-friendly electromagnetic wave absorbing materials with excellent thermal infrared stealth property,heat-insulating ability and compression resistance are highly attractive in practical applications.Meeting the afo... Eco-friendly electromagnetic wave absorbing materials with excellent thermal infrared stealth property,heat-insulating ability and compression resistance are highly attractive in practical applications.Meeting the aforesaid requirements simultaneously is a formidable challenge.Herein,ultra-light carbon aerogels were fabricated via fresh shaddock peel by facile freeze-drying method and calcination process,forming porous network architecture.With the heating platform temperature of 70℃,the upper surface temperatures of the as-prepared carbon aerogel present a slow upward trend.The color of the sample surface in thermal infrared images is similar to that of the surroundings.With the maximum compressive stress of 2.435 kPa,the carbon aerogels can provide favorable endurance.The shaddock peel-based carbon aerogels possess the minimum reflection loss value(RLmin)of−29.50 dB in X band.Meanwhile,the effective absorption bandwidth covers 5.80 GHz at a relatively thin thickness of only 1.7 mm.With the detection theta of 0°,the maximum radar cross-sectional(RCS)reduction values of 16.28 dB m^(2) can be achieved.Theoretical simulations of RCS have aroused extensive interest owing to their ingenious design and time-saving feature.This work paves the way for preparing multi-functional microwave absorbers derived from biomass raw materials under the guidance of RCS simulations. 展开更多
关键词 Microwave absorption Thermal insulation carbon aerogel Radar cross-sectional simulation Multi-function
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Structural Engineering of Hierarchical Aerogels Comprised of Multi-dimensional Gradient Carbon Nanoarchitectures for Highly Efficient Microwave Absorption 被引量:19
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作者 Yongpeng Zhao Xueqing Zuo +11 位作者 Yuan Guo Hui Huang Hao Zhang Ting Wang Ningxuan Wen Huan Chen Tianze Cong Javid Muhammad Xuan Yang Xinnan Wang Zeng Fan Lujun Pan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第9期344-363,共20页
Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing imped... Recently,multilevel structural carbon aerogels are deemed as attractive candidates for microwave absorbing materials.Nevertheless,excessive stack and agglomeration for low-dimension carbon nanomaterials inducing impedance mismatch are significant challenges.Herein,the delicate“3D helix-2D sheet-1D fiber-0D dot”hierarchical aerogels have been successfully synthesized,for the first time,by sequential processes of hydrothermal self-assembly and in-situ chemical vapor deposition method.Particularly,the graphene sheets are uniformly intercalated by 3D helical carbon nanocoils,which give a feasible solution to the mentioned problem and endows the as-obtained aerogel with abundant porous structures and better dielectric properties.Moreover,by adjusting the content of 0D core-shell structured particles and the parameters for growth of the 1D carbon nanofibers,tunable electromagnetic properties and excellent impedance matching are achieved,which plays a vital role in the microwave absorption performance.As expected,the optimized aerogels harvest excellent performance,including broad effective bandwidth and strong reflection loss at low filling ratio and thin thickness.This work gives valuable guidance and inspiration for the design of hierarchical materials comprised of dimensional gradient structures,which holds great application potential for electromagnetic wave attenuation. 展开更多
关键词 Hierarchical aerogels Multi-dimensional gradient carbon nanocoils Microwave absorption
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Controllable fabrication of carbon aerogels 被引量:2
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作者 TANEMURA Sakae TANEMURA Masaki SUZUKI Kenzi 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期284-288,共5页
Nano-pore carbon aerogels were prepared by the sol-gel polymerization of resorcinol (1,3-dihydroxybenzene)(C6H4(OH)2) with formaldehyde (HCHO) in a slightly basic aqueous solution, followed by super-critical drying un... Nano-pore carbon aerogels were prepared by the sol-gel polymerization of resorcinol (1,3-dihydroxybenzene)(C6H4(OH)2) with formaldehyde (HCHO) in a slightly basic aqueous solution, followed by super-critical drying under liquid carbon dioxide as super-critical media and carbonization at 700 ℃ under N2 gas atmosphere. The key of the work is to fabricate carbon aerogels with controllable nano-pore structure, which means extremely high surface area and sharp pore size distribution. Aiming to investigate the effects of preparation conditions on the gelation process, the bulk density, and the physical and chemical structure of the resultant carbon aerogels, the molar ratio of R/C (resorcinol to catalyst) and the amount of distilled water were varied, consequently two different sets of samples, with series of R/C ratio and RF/W (Resorcinol-Formaldehyde to water, or the content of reactant) ratio, were prepared. The result of N2 adsorption/desorption experiment at 77 K shows that the pore sizes decreasing from 11.4 down to 2.2 nm with the increasing of the molar ratio of R/C from 100 to 400, and/or, the pore sizes decreasing from 3.8 down to 1.6 nm with the increasing of reactant content from 0.4 to 0.6. 展开更多
关键词 resorcinol-formaldehyde aerogels carbon aerogels super-critical drying N2 adsorption/desorption
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Nitrogen-doped hierarchical porous carbon derived from metal–organic aerogel for high performance lithium–sulfur batteries 被引量:3
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作者 Han Zhang Zongbin Zhao +5 位作者 Yang Liu Jingjing Liang Yanan Hou Zhichao Zhang Xuzhen Wang Jieshan Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1282-1290,共9页
Nitrogen-doped three-dimensional(3 D) porous carbon materials have numerous applications due to their highly porous structures, abundant structural nitrogen heteroatom decoration and low densities. Herein,nitrogen dop... Nitrogen-doped three-dimensional(3 D) porous carbon materials have numerous applications due to their highly porous structures, abundant structural nitrogen heteroatom decoration and low densities. Herein,nitrogen doped hierarchical 3 D porous carbons(NHPC) were prepared via a novel metal–organic aerogel(MOA), using hexamethylenetetramine(HMT), 1,3,5-benzenetricarboxylic acid and copper(II) as starting materials. The morphology, porous structure of the building blocks in the NHPC can be tuned readily using different amount of HMT, which makes elongation of the pristine octahedron of HKUST-1 to give rise to different aspect ratio rod-like structures. The as-prepared NHPC with rod-like carbons exhibit high performance in lithium sulfur battery due to the rational ion transfer pathways, high N-doped doping and hierarchical porous structures. As a result, the initial specific capacity of 1341 m A h/g at rate of 0.5 C(1 C = 1675 m A h/g) and high-rate capability of 354 m A h/g at 5 C was achieved. The decay over 500 cycles is 0.08% per cycle at 1 C, highlighting the long-cycle Li–S batteries. 展开更多
关键词 Metal–organic aerogel N-doped porous carbon Lithium–sulfur batteries
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Preparation of CuO-CoO-MnO/SiO_2 Nanocomposite Aerogels as Catalyst Carriers and Their Application in the Synthesis of Diphenyl Carbonate 被引量:2
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作者 赵越卿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期595-599,共5页
CuO-CoO-MnO/SiO2 nanocomposite aerogels were prepared by using tetraethyl orthosilicate (TEOS) as Si source, and aqueous solution of Cu, Co and Mn acetates as transition metal sources via sol-gel process and supercr... CuO-CoO-MnO/SiO2 nanocomposite aerogels were prepared by using tetraethyl orthosilicate (TEOS) as Si source, and aqueous solution of Cu, Co and Mn acetates as transition metal sources via sol-gel process and supercritical drying (SCD) technique. The effect of synthesis conditions on gelation was investigated. Moreover, the composition of the CuO-CoO-MnO/SiO2 nanocomposite aerogels was characterized by electron dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), and the specific surface area of the nanocomposite aerogels was determined by the Brunauer-Emmett-Teller (BET) method. Diphenyl carbonate (DPC) as the product was analyzed by gas chromatography (GC). The experimental results show that the range of optimal temperature for gelation is 30-45 ℃, and the pH is 3.0-4.5. CuO-CoO-MnO/SiO2 nanocomposite aerogels are porous with a specific surface area of 384.9-700.6 m2/g. Compared to CO2 SCD, ethanol SCD is even favorable to the formation of aerogel with high specific surface area. The transition metals content in the nanocomposite aerogels can be controlled to be 0.71at%-13.77at%. With CuO-CoO-MnO/SiO2 nanocomposite aerogels as catalyst carrier, the yield of DPC is in direct proportion to the atomic fraction of transition metals in the nanocomposite aerogels, and it is up to 26.31 mass%, which is much higher than that via other porous carriers. 展开更多
关键词 composite aerogel PREPARATION catalyst carrier diphenyl carbonate
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Carbon aerogels for electric double-layer capacitors 被引量:1
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作者 ZHANG Lin LIU Hongbo WANG Ming LIU Wei 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期51-57,共7页
In this study, carbon aerogels were derived via the pyrolysis of resorcinol-formaldehyde (RF) aerogels, which were cost-effectively manufactured from RF wet gels by an ambient drying technique instead of conventional ... In this study, carbon aerogels were derived via the pyrolysis of resorcinol-formaldehyde (RF) aerogels, which were cost-effectively manufactured from RF wet gels by an ambient drying technique instead of conventional supercritical drying. By varying the R/C ratio (molar ratio of resorcinol to catalyst), mesoporous carbon aerogels with high specific surface area were prepared successfully and further investigated as electrode materials for electric double-layer capacitors (EDLCs). The textural properties of carbon aerogels obtained were characterized by nitrogen adsorption/desorption analysis and SEM. The electrochemical performances of carbon aerogels were investigated by impedance spectroscopy, galvanostatic charge/discharge and cyclic voltammetry methods. The results show that BET surface area and specific capacitance increase with R/C ratio, the maximum values of 727 m2·g-1 and 132 F·g-1 are achieved at R/C ratio will of 300. Increasing R/C ratio increase the average pore size of carbon aerogel electrode, which has improved the rate capability. Furthermore, EDLC with carbon aerogel electrodes has an excellent stability at large discharge current and long cycle life. 展开更多
关键词 carbon aerogel electric double-layer capacitors TEXTURE electrochemical performance
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Structural evolution of carbon aerogel microspheres by thermal treatment for high–power supercapacitors 被引量:1
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作者 Feng Li Lijing Xie +5 位作者 Guohua Sun Fangyuan Su Qingqiang Kong Yufang Cao Xiangyun Guo Chengmeng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期439-446,共8页
In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. Th... In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. The effects of heat-treatment temperature(HTT) on the CAM microstructure were systematically investigated by physical and chemical characterization. The electrical conductivity increased by up to 250 S/cm and mesopores with high electrolyte accessibility developed in the CAM with increasing HTT. However, the specific surface area(SSA) decreased for HTTs from 1000 to 1600 ℃. The results show that these two factors should be finely balanced for further applications in high power supercapacitors.The CAMs carbonized at 1000 ℃ had the highest SSA(1454 m^2/g), large mesoporous content(20%) and favorable conductivity(71 S/cm). They delivered a high energy density of 38.4 Wh/kg at a power density of 0.17 kW/kg. They retained an energy density of 25.5 Wh/kg even at a high power density of 10.2 kW/kg,and a good rate capability of 84% after 10,000 cycles. This performance is superior to, or at least comparable to, those of most reported carbon materials. 展开更多
关键词 carbon aerogel microspheres Heat-treatment temperature Physical/chemical changes CONDUCTIVITY SUPERcaPACITOR
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Role of Catalyst on the Formation of Resorcinol-Furfural Based Carbon Aerogels and Its Physical Properties 被引量:2
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作者 Karumully S. Rejitha Poovakulathu A. Abraham +2 位作者 Narayana P. R. Panicker Kollanoor S. Jacob Nimai C. Pramanik 《Advances in Nanoparticles》 2013年第2期99-103,共5页
Carbon aerogels (CAG) were synthesized by the pyrolysis of resorcinol-furfural based organic aerogels, derived from sol-gel polymerization of resorcinol and furfural using different catalysts followed by supercritical... Carbon aerogels (CAG) were synthesized by the pyrolysis of resorcinol-furfural based organic aerogels, derived from sol-gel polymerization of resorcinol and furfural using different catalysts followed by supercritical drying of as-prepared gels. Different catalysts viz. hydrochloric acid (HA), acetic acid (AcH) and hexamethylenetetramine (HMTA) of different concentrations were used for this purpose in order to study the role of different catalysts and the effect of R/C ratio (reactant to catalyst molar ratio) on the formation of organic gel monolith and their physical properties were investigated. Aerogels were thoroughly characterized by using CHN, FTIR, TG-DSC, XRD and SEM. A considerable reduction of gelation time and the formation of relatively denser organic gel were observed in the case of HMTA, which indicated the dual role (catalyst & cross-linking agent) of HMTA during the polymerization/polycondensation of resorcinol and furfural. Carbon aerogels obtained by using different catalysts showed BET surface area, average pore size, total pore volumes in the range of 438 496 m2/g, 17.9 22.4 ? and 0.20 0.27 cm3/g, respectively. The SEM images and results revealed the presence of different morphologies of carbon aerogels, obtained by using different catalysts. The HMTA catalyzed samples were found to have highest surface area with particles in smaller in size and well interconnected 3D carbon network. 展开更多
关键词 carbon aerogel SUPERCRITIcaL Drying Sol-Gel Synthesis ROLE of caTALYST Surface area Analysis Pore Characteristics
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S-doped carbon aerogels/GO composites as oxygen reduction catalysts 被引量:3
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作者 Mykola Seredych Krisztina László +1 位作者 Enrique Rodríguez-Castellón Teresa J.Bandosz 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第2期234-243,共10页
Composites of carbon aerogel and graphite oxide(GO) were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples... Composites of carbon aerogel and graphite oxide(GO) were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions(ORR) in an alkaline medium.The synergistic effect of the composite(electrical conductivity, porosity and surface chemistry) leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded. 展开更多
关键词 Oxygen reduction reaction carbon aerogel/GO composites Porosity Surface chemistry Specific interactions
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Biomass Carbon Aerogel Modified by N235 and KH560 for Removal of Iodide from Oilfield Brine 被引量:1
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作者 HU Yaoqiang GUO Min +2 位作者 YE Xiushen LIU Haining WU Zhijian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第4期608-619,共12页
Owing to porous structure,stable chemical properties,low cost and available raw material,biomass carbon aerogel is a promising adsorbent framework material.Herein,a pomelo peel-based carbon aerogel was prepared by hyd... Owing to porous structure,stable chemical properties,low cost and available raw material,biomass carbon aerogel is a promising adsorbent framework material.Herein,a pomelo peel-based carbon aerogel was prepared by hydrothermal-freeze drying-high temperature carbonization method and modified with Tri-n-ocylamine(N235)and γ-Glycidyloxypropyltrimethoxysilane(KH560)via impregnation process.The as-prepared adsorbents exhibit superior adsorption performance for iodide in simulated and oilfield brines,and the highest adsorption amount of iodide in oilfield brine can reach 0.58 mmol/g.It is also demonstrated by adsorption kinetics and isotherms that iodide is adsorbed through chemical adsorption.Protonation of tertiary amide group in N235 and epoxy group in KH560 may be the main reason for the highly selective adsorption of iodide. 展开更多
关键词 biomass carbon aerogel oilfield brine IODIDE ADSORPTION
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THE FABRICATION OF CARBON AEROGELS BY GELATION IN ISOPROPANOL WITH BASIC CATALYST 被引量:1
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作者 WU Dingcai ZHANG Shuting FU Ruowen 《Chinese Journal of Reactive Polymers》 2003年第1期26-31,共6页
A new method for the fabrication of carbon aerogels is reported in this paper. Resorcinol and furfural were gelated in isopropanol with basic catalysts and then dried directly under isopropanol supercritical condition... A new method for the fabrication of carbon aerogels is reported in this paper. Resorcinol and furfural were gelated in isopropanol with basic catalysts and then dried directly under isopropanol supercritical condition, followed by carbonization under nitrogen atmosphere. The bulk densities of carbon aerogels obtained are in the range of 0.21g/cm3~0.27g/cm3 and the sizes of the interconnected carbon nano-particles are in the range of 20nm^30nm. All of the aerogel samples exhibit high BET surface areas in the range of 730m2/g^900m2/g. The bulk density, micro-pore volume, meso-pore volume and meso-pore diameter can be controlled by gelation conditions such as R/I ratio and R/C ratio. 展开更多
关键词 carbon aerogel Basic catalyst Isopropanol supercritical drying
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