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...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.展开更多
Lithium-selenium(Li-Se)battery has attracted growing attention.Nevertheless,its practical application is still impeded by the shuttle effect of the formed polyselenides.Herein,we report in-situ hydrothermal weaving th...Lithium-selenium(Li-Se)battery has attracted growing attention.Nevertheless,its practical application is still impeded by the shuttle effect of the formed polyselenides.Herein,we report in-situ hydrothermal weaving the three-dimensional(3 D)highly conductive hierarchically interconnected nanoporous web by threading microporous metal organic framework MIL-68(Al)crystals onto multi-walled carbon nanotubes(MWCNTs).Such 3 D hierarchically nanoporous web(3 D MIL-68(Al)@MWCNTs web)with a very high surface area,a large amount of micropores,electrical conductivity and elasticity strongly traps the soluble polyselenides during the electrochemical reaction and significantly facilitates lithium ion diffusion and electron transportation.Molecular dynamic calculation confirmed the strong affinity of MIL-68(Al)for the adsorption of polyselenides,quite suitable for Li-Se battery.Their hexahedral channels(1.56 nm)are more efficient for the confinement of polyselenides and for the diffusion of electrolytes compared to their smaller triangular channels(0.63 nm).All these excellent characteristics of 3 D MIL-68(Al)@MWCNTs web with suitable confinement of a large amount of selenium and the conductive linkage between MIL-68(Al)host by MWCNTs result in a high capacity of 453 m Ah/g at 0.2 C with 99.5%coulombic efficiency after 200 cycles with significantly improved cycle stability and rate performance.The 3 D MIL-68(Al)@MWCNTs web presents a good performance in Li-Se battery in term of the specific capacity and cycling stability and also in terms of rate performance compared with all the metal-organic framework(MOF)based or MOF derived porous carbons used in Li-Se battery.展开更多
In order to find the appropriate material to load selenium for higher performance of rechargeable Li-Se batteries,the resorcinol-formaldehyde resins derived monodisperse carbon spheres(RFCS)/Se composites were fabrica...In order to find the appropriate material to load selenium for higher performance of rechargeable Li-Se batteries,the resorcinol-formaldehyde resins derived monodisperse carbon spheres(RFCS)/Se composites were fabricated by the melting-diffusion method.The RFCS were obtained from initial carbonization of resorcinol-formaldehyde resins and subsequent KOH activation.Three kinds of samples of the RFCS/Se composites with different mass ratios were characterized by XRD,Raman spectroscopy,SEM,BET and EDS tests,which demonstrate that the samples with diverse mass fractions of selenium have distinct interior structure.The most suitable RFCS/Se composite is found to be the RFCS/Se-50 composite,which delivers a high reversible capacity of 643.9 mA·h/g after 100 cycles at current density of 0.2C.展开更多
基金financially supported by the National Key R&D Program of China(Grants 2016YBF0100100,2016YFA0200200)the National Natural Science Foundation of China(Grants 51872283,21805273)+1 种基金the Liaoning Bai Qian Wan Talents Program,Natural Science Foundation of Liaoning Province,Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(Grant 20180510038)the Liao Ning Revitalization Talents Program(Grant XLYC1807153),DICP(DICP ZZBS201708,DICP ZZBS201802,DICP I202032),DNL Cooperation Fund,CAS(DNL180310,DNL180308,DNL201912,and DNL201915),DICP&QIBEBT(Grant DICP&QIBEBT UN201702)。
文摘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.
基金supported by the National Postdoctoral Program(2020M672782)National Natural Science Foundation of China(No.U1663225)+2 种基金Changjiang Scholars and Innovative Research Team in University(No.IRT15R52)National 111 project from the Ministry of Science and Technologythe Ministry of Education of China and the National Key R&D Program of China(No.2016YFA0202602)。
文摘Lithium-selenium(Li-Se)battery has attracted growing attention.Nevertheless,its practical application is still impeded by the shuttle effect of the formed polyselenides.Herein,we report in-situ hydrothermal weaving the three-dimensional(3 D)highly conductive hierarchically interconnected nanoporous web by threading microporous metal organic framework MIL-68(Al)crystals onto multi-walled carbon nanotubes(MWCNTs).Such 3 D hierarchically nanoporous web(3 D MIL-68(Al)@MWCNTs web)with a very high surface area,a large amount of micropores,electrical conductivity and elasticity strongly traps the soluble polyselenides during the electrochemical reaction and significantly facilitates lithium ion diffusion and electron transportation.Molecular dynamic calculation confirmed the strong affinity of MIL-68(Al)for the adsorption of polyselenides,quite suitable for Li-Se battery.Their hexahedral channels(1.56 nm)are more efficient for the confinement of polyselenides and for the diffusion of electrolytes compared to their smaller triangular channels(0.63 nm).All these excellent characteristics of 3 D MIL-68(Al)@MWCNTs web with suitable confinement of a large amount of selenium and the conductive linkage between MIL-68(Al)host by MWCNTs result in a high capacity of 453 m Ah/g at 0.2 C with 99.5%coulombic efficiency after 200 cycles with significantly improved cycle stability and rate performance.The 3 D MIL-68(Al)@MWCNTs web presents a good performance in Li-Se battery in term of the specific capacity and cycling stability and also in terms of rate performance compared with all the metal-organic framework(MOF)based or MOF derived porous carbons used in Li-Se battery.
基金Project(21471162)supported by the National Natural Science Foundation of ChinaProject supported by the Recruitment Program of Global Youth Experts,ChinaProject(20130162120031)supported by Research Fund for the Doctoral Program of Higher Education of China
文摘In order to find the appropriate material to load selenium for higher performance of rechargeable Li-Se batteries,the resorcinol-formaldehyde resins derived monodisperse carbon spheres(RFCS)/Se composites were fabricated by the melting-diffusion method.The RFCS were obtained from initial carbonization of resorcinol-formaldehyde resins and subsequent KOH activation.Three kinds of samples of the RFCS/Se composites with different mass ratios were characterized by XRD,Raman spectroscopy,SEM,BET and EDS tests,which demonstrate that the samples with diverse mass fractions of selenium have distinct interior structure.The most suitable RFCS/Se composite is found to be the RFCS/Se-50 composite,which delivers a high reversible capacity of 643.9 mA·h/g after 100 cycles at current density of 0.2C.