检索结果-南通市图书馆

Fabrication of monodispersed B,N co-doped hierarchical porous carbon nanocages through confined etching to boost electrocatalytic oxygen reduction

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第1期16卷 290-298页

作者： Xuefei Wang Chao Han Haitao Li Panpan Su Na Ta Yanfu Ma Zhenguo Huang Jian Liu School of Civil&Environmental Engineering University of Technology SydneySydneyNSW2007Australia State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China DICP-Surrey Joint Centre for Future Materials University of Surrey GuildfordSurreyGU27XHUK

Dual heteroatom-doped carbons have attracted widespread research attention as catalysts in the field of energy storage and conversion due to their unique electronic structures and chemical tunability.In particular,boron and nitrogen co-doped carbon(B,N@C)has shown great potential for photo/electrocatalytic applications.However,more needs to be done for rational designing and regulating the structure of these materials to improve their catalytic performance.Herein,monodispersed hierarchical porous B,N@C nanocages were fabricated by pyrolyzing zeolite imidazole framework(ZIF)which was treated with ammonia borane or boric acid via an integrated double-solvent impregnation and nanocofined-etching method.The treated ZIF-8 provided an essential structural template to achieve B,N co-doped hierarchical structures with micro/meso/macro multimodal pore size distributions.The resultant B,N@C nanocages displayed high catalytic activities for electrochemical oxygen reduction reaction(ORR)in alkaline media,outperforming most carbon-based catalysts,particularly from the perspective of the half-wave potentials.Such high catalytic performance is due to the enhanced activity by the coexistence of B and N and the mass transfer promoted by the unique hierarchical porous structure.

关键词： heteroatom doping hierarchical porous carbon host-guest chemistry confined etching electrocatalysis mass transfer

Synthesis of hierarchical porous carbon with high surface area by chemical activation of(NH_(4))_(2)C_(2)O_(4) modified hydrochar for chlorobenzene adsorption

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第4期126卷 123-137页

作者： Jie Wen Zewei Liu Hongxia Xi Bichun Huang School of Environment and Energy South China University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSouth China University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006China

In this work,hydrothermal technique combined with KOH activation were employed to develop a series of porous carbons (NPCK-x) using tobacco stem as a low-cost carbon source and (NH_(4))_(2)C_(2)O_(4)as a novel nitrogen-doping agent.Physicochemical properties of NPCK-x were characterized by Brunauer-Emmett-Teller,field emission scanning electron microscopy,X-ray diffraction,Raman microscope,elemental analysis,and X-ray photoelectron spectroscopy.Results showed that the NPCK-x samples possessed large surface areas (maximum:2875 m^(2)/g),hierarchical porous structures,and high degree of disorder.N-containing functional groups decomposed during activation process,which could be the dominant reason for appearance of abundant mesopores and well-developed pore structure.Dynamic chlorobenzene adsorption experiments demonstrated that carbon materials with(NH_(4))_(2)C_(2)O_(4)modification exhibited higher adsorption capacity (maximum:1053 mg/g) than those without modification (maximum:723 mg/g).The reusability studies of chlorobenzene indicated that the desorption efficiency of (NH_(4))_(2)C_(2)O_(4)modified porous carbon reached90.40%after thermal desorption at 100℃ under N2atmosphere.Thomas model fitting results exhibited that the existence of mesopores accelerated the diffusion rate of chlorobenzene in porous carbon.Moreover,Grand Canonical Monte Carlo simulation was conducted to verify that micropores with pore sizes of 1.2–2 nm of the optimized porous carbon were the best adsorption sites for chlorobenzene and mesopores with pore sizes of 2–5 nm were also highly active sites for chlorobenzene adsorption.

关键词： Tobacco stem hierarchical porous carbon N-containing groups Dynamic adsorption Chlorobenzene

Edge-enriched N, S co-doped hierarchical porous carbon for oxygen reduction reaction

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第2期34卷 349-354页

作者： Fangfang Chang Panpan Su Utsab Guharoy Runping Ye Yanfu Ma Huajun Zheng Yi Jia Jian Liu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Chemistry and Zhejiang carbon Neutral Innovation Institute Zhejiang University of TechnologyHangzhou 310032China DICP-Surrey Joint Centre for Future Materials Department of Chemical and Process EngineeringUniversity of SurreyGuildfordSurrey GU27XHUnited Kingdom

The development of carbon materials with high electrochemical performance for next-generation energy device is emerging, especially N, S co-doped carbon materials have sparked intensive attention. However,the exploration of N, S co-doped carbon with well-defined active sites and hierarchical porous structures are still limited. In this study, we prepared a series of edge-enriched N, S co-doped carbon materials through pyrolysis of thiourea(TU) encapsulated in zeolitic imidazolate frameworks(TU@ZIF) composites,which delivered very good oxygen reduction reaction(ORR) performance in alkaline medium with onset potential of 0.94 V vs. reversible hydrogen electrode(RHE), good stability and methanol tolerance. Density functional theory(DFT) calculations suggested that carbon atoms adjacent to N and S are probable active sites for ORR intermediates in edge-enriched N, S co-doped carbon materials because higher electron density can enhance O_(2)adsorption, lower formation barriers of intermediates, improving the ORR performance comparing to intact N, S co-doped carbon materials. This study might provide a new pathway for improving ORR activity by the integration engineering of edge sites, and electronic structure of heteroatom doped carbon electrocatalysts.

关键词： Porosity engineering N S co-doped carbon materials hierarchical porous carbon Edge-enriched carbon Oxygen reduction reaction DFT calculation

Status and perspectives of hierarchical porous carbon materials in terms of high-performance lithium-sulfur batteries

在线全文

学校读者我要写书评

暂无评论

carbon Energy 2022年第3期4卷 346-398页

作者： Yinyu Xiang Liqiang Lu Ajay Giri Prakash Kottapalli Yutao Pei Advanced Production Engineering(APE) Engineering and Technology Institute Groningen(ENTEG)Faculty of Science and EngineeringUniversity of Groningen9747 AGGroningenThe Netherlands

Lithium-sulfur(Li-S)batteries,although a promising candidate of next-generation energy storage devices,are hindered by some bottlenecks in their roadmap toward commercialization.The key challenges include solving the issues such as low utilization of active materials,poor cyclic stability,poor rate performance,and unsatisfactory Coulombic efficiency due to the inherent poor electrical and ionic conductivity of sulfur and its discharged products(e.g.,Li2S2 and Li_(2)S),dissolution and migration of polysulfide ions in the electrolyte,unstable solid electrolyte interphase and dendritic growth on an odes,and volume change in both cathodes and anodes.Owing to the high specific surface area,pore volume,low density,good chemical stability,and particularly multimodal pore sizes,hierarchical porous carbon(HPC)mate rials have received considerable attention for circumventing the above pro blems in Li-S batteries.Herein,recent progress made in the synthetic methods and deployment of HPC materials for various components including sulfur cathodes,separators and interlayers,and lithium anodes in Li-S batteries is presented and summarized.More importantly,the correlation between the structures(pore volume,specific surface area,degree of pores,and heteroatom-doping)of HPC and the electrochemical performances of Li-S batteries is elaborated.Finally,a discussion on the challenges and future perspectives associated with HPCs for Li-S batteries is provided.

关键词： carbon/sulfur cathodes hierarchical porous carbon lithium-sulfur batteries lithium metal anodes separators/interlayers synthetic methods

hierarchical porous carbon toward effective cathode in advanced zinc-cerium redox flow battery

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2014年第10期32卷 973-978页

作者：谢志鹏杨斌蔡定建杨亮 College of Chemistry and Chemical Engineering Jiangxi University of Science and Technology State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of Sciences

Advanced zinc-cerium redox flow battery（ZCRFB） is a large-scale energy storage system which plays a significant role in the application of new energy sources. The requirement of superior cathode with high acitivity and fast ion diffusion is a hierarchical porous structure, which was synthesized in this work by a method in which both hard template and soft template were used. The structure and the performance of the cathode prepared here were characterized and evaluated by a variety of techniques such as scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, X-ray photoelectron spectroscopy（XPS）, cyclic voltammetry（CV）, linear sweep voltammetry（LSV）, and chronoamperometry（CA）. There were mainly three types of pore size within the hierarchical porous carbon： 2 μm, 80 nm, and 10 nm. The charge capacity of the cell using hierarchical porous carbon（HPC） as positive electrode was obviously larger than that using carbon felt; the former was 665.5 mAh with a coulombic efficiency of 89.0% and an energy efficiency of 79.0%, whereas the latter was 611.1 mAh with a coulombic efficiency of 81.5% and an energy efficiency of 68.6%. In addition, performance of the ZCRFB using HPC as positive electrode showed a good stability over 50 cycles.These results showed that the hierarchical porous carbon was superior over the carbon felt for application in ZCRFB.

关键词： new energy energy storage redox flow battery hierarchical porous carbon cerium carbon felt electrode electrolyte rare earths

hierarchical and lamellar porous carbon as interconnected sulfur host and polysulfide-proof interlayer for Li–S batteries

在线全文

学校读者我要写书评

暂无评论

eScience 2023年第1期3卷 89-98页

作者： Peifan Wang Xin Dai Peng Xu Sijiang Hu Xuyang Xiong Kunyang Zou Shengwu Guo Junjie Sun Chaofeng Zhang Yongning Liu Tengfei Zhou Yuanzhen Chen The State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049PR China Technical Monitoring Center Petro China Changqing Oil Field CompanyXi'an710018PR China Guangxi Key Laboratory of Low carbon Energy Material Guangxi Normal UniversityGuilin541004China Institutes of Physical Science and Information Technology Anhui UniversityHefei230601PR China

A robust three-dimensional(3D)interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries.Herein,cellulose-based 3D hierarchical porous carbon(HPC)and two-dimensional(2D)lamellar porous carbon(LPC)are employed as the sulfur host and polysulfide-proof inter-layer,respectively,for a Li–S battery.The 3D HPC displays a cross-linked macroporous structure,which allows high sulfur loading and restriction capability and provides unobstructed electrolyte diffusion channels.With a stackable carbon sheet of 2D LPC that has a large plane view size and is ultrathin and porous,the LPC-coated separator effectively inhibits polysulfides.An optimized combination of the HPC and LPC yields an electrode structure that effectively protects the lithium anode against corrosion by polysulfides,giving the cell a high ca-pacity of 1339.4 mAh g^(-1) and high stability,with a capacity decay rate of 0.021% per cycle at 0.2C.This work provides a new understanding of biomaterials and offers a novel strategy to improve the performance of Li–S batteries for practical applications.

关键词： Lithium-sulfur batteries hierarchical porous carbon Lamellar porous carbon Interconnected sulfur host Polysulfide-proof interlayer

hierarchical porous carbon derived from Allium cepa for supercapacitors through direct carbonization method with the assist of calcium acetate

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2017年第12期28卷 2295-2297页

作者： Jinhui Xu Wenli Zhang Dianxun Hou Weimin Huang Haibo Lin College of Chemistry Jilin UniversityChangchun 130012China Department of Civii Environmentaland Architectural EngineeringUniversity of Colorado BoulderBoulder CO 80309USA Guangdong Guanghua Sci-Tech Co. Ltd.Shantou 515061China

In this paper, a direction carbonization method was used to prepare porous carbon from Allium cepa for supercapacitor applications. In this method, calcium acetate was used to assist carbonization process. Scanning electron microscope （SEM） and N2 adsorption/desorption method were used to characterize the morphology, Brunauer-Emmett-Teller （BET） specific surface area and pore size distribution of porous carbon derived from Allium cepa （onion derived porous carbon, OPC）. OPC is of hierarchical porous structure with high specific surface area and relatively high specific capacitance. OPC possesses relatively high specific surface area of 533.5 m2Jg. What＇s more, OPC possesses a specific capacitance of 133.5 Fig at scan rate of 5 mV/s.

关键词： porous carbon Supercapacitor Allium cepa hierarchical porous carbon Direct pyrolysis Biomass

Lignin derived hierarchical porous carbon with extremely suppressed polyselenide shuttling for high-capacity and long-cycle-life lithium-selenium batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第4期30卷 476-483页

作者： Pengfei Lu Fangyan Liu Feng Zhou Jieqiong Qin Haodong Shi Zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China

Lithium-selenium(Li-Se)batteries have attracted considerable attentions for next-generation energy storage systems owing to high volumetric capacity of 3265 m Ah cm^(-3) and excellent electronic conductivity(~10^(-5)S cm^(-1))of selenium.However,the shuttling effect and capacity fading prevent their wide applications.Herein we report a low-cost strategy for scalable fabrication of lignin derived hierarchical porous carbon(LHPC)as a new high-loading Se host for high-capacity and long-term cycling Li-Se batteries in carbonate electrolyte.The resulting LHPC exhibits three-dimensional(3D)hierarchically porous structure,high specific surface area of 1696 m^(2) g^(-1),and hetero-atom doping(O,S),which can effectively confine the Se particles into the micropores,and meanwhile,offer effective chemical binding sites for selenides from hetero-atoms(O,S).As a result,our Li-Se batteries based on Se@LHPC demonstrate high capacity of 450 m Ah g^(-1) at 0.5 C after 500 cycles,with a low capacity fading rate of only 0.027%.The theoretical simulation confirmed the strong affinity of selenides on the O and S sites of LHPC effectively mitigating the Se losing.Therefore,our strategy of using lignin as the low-cost precursor of hierarchically porous carbon for high-loading Se host offers new opportunities for high-capacity and long-life Li-Se batteries.

关键词： Lignin hierarchical porous carbon Lithium selenium battery Long cycling stability Energy storage

Effects of annealing temperature on electrochemical performance of SnSx embedded in hierarchical porous carbon with N-carbon coating by in-situ structural phase transformation as anodes for lithium ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第25期84卷 191-199页

作者： Qianqian Hu Biao Wang Shiyong Chang Chun Yang Yunjian Hu Shubin Cao Jiqun Lu Lingzhi Zhang Ye Hong Guangzhou Institute of Energy Conversion Chinese Academy of SciencesCAS Key Laboratory of Renewable EnergyGuangdong Provincial Key Laboratory of New and Renewable Energy Research and DevelopmentGuangzhouGuangdong 510640China GAC Automotive Research&Development Center Guangzhou 511434China University of Chinese Academy of Sciences Beijing 100049China Nano Science and Technology Institute University of Science and Technology of ChinaSuzhou 215123China Industrial Training Center Guangdong Polytechnic Normal University510665China

Tuned tin chalcogenides rooted in hierarchical porous carbon(HPC)with N-carbon coating layers are prepared by thermal shock under various temperatures(denoted as HPC-SnS_(2)-PAN-Various T).With the increase of annealing temperature,the morphology and phase structure of Sn S_(2),as well as the cyclization degree of polyacrylonitrile(PAN),are significantly changed,which leads to the formation of rod-like Sn S and ordered structure of conductive N-carbon layer.By combining HPC,N-carbon coating derived from the cyclization of PAN,with 1D Sn S nanorods generated from structural phase transformation of SnS_(2),the optimized composite(HPC-SnS_(2)-PAN-500)as anode for lithium ion batteries(LIBs)provides buffer space for volume changes during alloying/dealloying process,builds a highly conductive network as well as decreases irreversible capacity from solid electrolyte interphase and enhances the ion/electron transport.Attributed to the above merits from composition regulation and architecture modification by sulfur depletion and PAN cyclization,this target anode exhibits an extraordinary cycling stability with a high specific capacity of 652.5 m A h/g at 0.5 A/g after 900 cycles.It suggests that rod-like Sn S embedded in HPC with cyclized PAN layers by thermal treatment approach renders a potential structural design of anode materials for LIBs.

关键词： hierarchical porous carbon SnSx Conducting medium Cycling stability Lithium ion batteries