Metal-organic framework(MOF)and its derivatives have low-cost,controllable structure,and good catalytic performance,which are often used in the electrochemical field.In this work,SnO_(2)in situ modified graphite felt(...Metal-organic framework(MOF)and its derivatives have low-cost,controllable structure,and good catalytic performance,which are often used in the electrochemical field.In this work,SnO_(2)in situ modified graphite felt(SnO_(2)/GF)is prepared by hydrothermal method then simple thermal treatment using Sn-based MOF(Sn-MOF)as precursor.SnO_(2)is uniformly and firmly distributed on the GF surface rather than the common agglomeration and poor bonding of metal oxides on carbon-based electrodes,providing stable active centers for the VO^(2+)/VO_(2)^(+)and V^(2+)/V^(3+)redox reactions.At250 mA·cm^(-2),the energy efficiency of the battery with SnO_(2)/GF remains at 63.2%,while the blank one has failed.The former battery,at 100 mA·cm^(-2),has higher energy efficiency and good cycle stability(over 200 cycles).The battery performance of this study is better than that of most previous report in metal oxide-related work.This work obtains high-performance composite electrode by simple treatment of MOF,which provides a reference for the application of MOF in vanadium redox flow battery.展开更多
A novel polybenzimidazole(PBI)-based trilayer membrane assembly is developed for application in vanadium redox flow battery(VRFB).The membrane comprises a 1μm thin cross-linked poly[2,2′-(p-oxydiphenylene)−5,5′-bib...A novel polybenzimidazole(PBI)-based trilayer membrane assembly is developed for application in vanadium redox flow battery(VRFB).The membrane comprises a 1μm thin cross-linked poly[2,2′-(p-oxydiphenylene)−5,5′-bibenzimidazole](OPBI)sandwiched between two 20μm thick porous OPBI membranes(p-OPBI)without further lamination steps.The trilayer membrane demonstrates exceptional properties,such as high conductivity and low area-specific resistance(ASR)of 51 mS cm^(−1) and 81mΩ cm^(2),respectively.Contact with vanadium electrolyte increases the ASR of trilayer membrane only to 158mΩ cm^(2),while that of Nafion is 193mΩ cm^(2).VO^(2+) permeability is 2.73×10^(-9) cm^(2) min^(−1),about 150 times lower than that of Nafion NR212.In addition,the membrane has high mechanical strength and high chemical stability against VO^(2+).In VRFB,the combination of low resistance and low vanadium permeability results in excellent performance,revealing high Coulombic efficiency(>99%),high energy efficiency(EE;90.8% at current density of 80mA cm^(−2)),and long-term durability.The EE is one of the best reported to date.展开更多
基金the National Natural Science Foundation of China(Nos.51872090 and 51772097)Hebei Natural Science Fund for Distinguished Young Scholar(No.E2019209433)+1 种基金the Youth Talent Program of Hebei Provincial Education Department(No.BJ2018020)the Natural Science Foundation of Hebei Province(No.E2020209151)。
文摘Metal-organic framework(MOF)and its derivatives have low-cost,controllable structure,and good catalytic performance,which are often used in the electrochemical field.In this work,SnO_(2)in situ modified graphite felt(SnO_(2)/GF)is prepared by hydrothermal method then simple thermal treatment using Sn-based MOF(Sn-MOF)as precursor.SnO_(2)is uniformly and firmly distributed on the GF surface rather than the common agglomeration and poor bonding of metal oxides on carbon-based electrodes,providing stable active centers for the VO^(2+)/VO_(2)^(+)and V^(2+)/V^(3+)redox reactions.At250 mA·cm^(-2),the energy efficiency of the battery with SnO_(2)/GF remains at 63.2%,while the blank one has failed.The former battery,at 100 mA·cm^(-2),has higher energy efficiency and good cycle stability(over 200 cycles).The battery performance of this study is better than that of most previous report in metal oxide-related work.This work obtains high-performance composite electrode by simple treatment of MOF,which provides a reference for the application of MOF in vanadium redox flow battery.
基金supported by KIST (2E31871 and 2E32591)and Innovation Fund Denmark Denmark (DANFLOW—project#9090-00059)Korea Institute for Advancement of Technology (KIAT)through the International Cooperative R&D program (Project No.P0018437)Basic Science Research Program through the National Research Foundation of Korea (NRF)funded by the Ministry of Education (2021R1A6A1A03039981).
文摘A novel polybenzimidazole(PBI)-based trilayer membrane assembly is developed for application in vanadium redox flow battery(VRFB).The membrane comprises a 1μm thin cross-linked poly[2,2′-(p-oxydiphenylene)−5,5′-bibenzimidazole](OPBI)sandwiched between two 20μm thick porous OPBI membranes(p-OPBI)without further lamination steps.The trilayer membrane demonstrates exceptional properties,such as high conductivity and low area-specific resistance(ASR)of 51 mS cm^(−1) and 81mΩ cm^(2),respectively.Contact with vanadium electrolyte increases the ASR of trilayer membrane only to 158mΩ cm^(2),while that of Nafion is 193mΩ cm^(2).VO^(2+) permeability is 2.73×10^(-9) cm^(2) min^(−1),about 150 times lower than that of Nafion NR212.In addition,the membrane has high mechanical strength and high chemical stability against VO^(2+).In VRFB,the combination of low resistance and low vanadium permeability results in excellent performance,revealing high Coulombic efficiency(>99%),high energy efficiency(EE;90.8% at current density of 80mA cm^(−2)),and long-term durability.The EE is one of the best reported to date.
