The commercialization of lithium-sulfur(Li-S)batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides(LiPSs).Herein,we reported a viologen-ba sed ionic conjugated mesoporou...The commercialization of lithium-sulfur(Li-S)batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides(LiPSs).Herein,we reported a viologen-ba sed ionic conjugated mesoporous polymer(TpV-Cl),which acts as the cathode host for modifying Li-S batteries.The viologen component serves as a reversible electron conveyer,leading to a comprehensive enhancement in the adsorption of polysulfides and improved conversion rate of polysulfides during the electrochemical process.As a result,the S@TpV-PS cathode exhibits outstanding cycling performance,achieving 300 cycles at2.0 C(1 C=1675 mA g^(-1))with low decay rate of 0.032%per cycle.Even at a high sulfur loading of 4.0 mg cm^(-2),S@TpV-PS shows excellent cycling stability with a Coulombic efficiency of up to 98%.These results highlight the significant potential of S@TpV-PS in developing high-performance Li-S batteries.展开更多
It was known that mesoporous metal-organic frameworks(MOFs)with hierarchical pores and unsaturated metal sites can effectively inhibit the shuttle effect of lithium polysulfides in lithium-sulfur battery,however,the u...It was known that mesoporous metal-organic frameworks(MOFs)with hierarchical pores and unsaturated metal sites can effectively inhibit the shuttle effect of lithium polysulfides in lithium-sulfur battery,however,the unsatisfactory structural stability and electrical conductivity limit the application of mesoporous MOFs(MMOFs)in Li-S batteries.Aiming at sensible solutions,the conductive polyaniline(PANI)was incorporated into the MMOF to enhance the discharge capacity and the cycling stability of proposed Li-S batteries,as the stability and the conductivity of the MMOF cathode was improved simultaneously.The activated MMOF-PANI provides physical and chemical adsorption of polysulfides against their shuttle effect.Moreover,the introduction of PANI into the channels of MMOF effectively improves the conductivity of MMOF,thus improving the electrochemical performance of the MMOF-PANI-based batteries.Benefiting from these synergetic effects,the S@MMOF-PANI cathode delivers improved electrochemical performance including excellent rate performance and cycling stability.The battery shows an initial capacity of 777.7 mAh·g^(−1)at 2.0 C and a low decay rate of 0.06%per cycle in 1,000 cycles and approximately a repeatable rate performance.展开更多
基金supported by the National Natural Science Foundation of China(21825106,92061201,22205210,and 22171248)the Zhongyuan Thousand Talents(Zhongyuan Scholars)Program of Henan Province(234000510007)+1 种基金the Natural Science Foundation of Henan Province(222300420289)Zhengzhou University。
文摘The commercialization of lithium-sulfur(Li-S)batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides(LiPSs).Herein,we reported a viologen-ba sed ionic conjugated mesoporous polymer(TpV-Cl),which acts as the cathode host for modifying Li-S batteries.The viologen component serves as a reversible electron conveyer,leading to a comprehensive enhancement in the adsorption of polysulfides and improved conversion rate of polysulfides during the electrochemical process.As a result,the S@TpV-PS cathode exhibits outstanding cycling performance,achieving 300 cycles at2.0 C(1 C=1675 mA g^(-1))with low decay rate of 0.032%per cycle.Even at a high sulfur loading of 4.0 mg cm^(-2),S@TpV-PS shows excellent cycling stability with a Coulombic efficiency of up to 98%.These results highlight the significant potential of S@TpV-PS in developing high-performance Li-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.21825106,92061201,and 21975065)the Natural Science Foundation of Henan Province(No.22230020289)the Henan Postdoctoral Science Foundation(No.202102002),and Zhengzhou University.
文摘It was known that mesoporous metal-organic frameworks(MOFs)with hierarchical pores and unsaturated metal sites can effectively inhibit the shuttle effect of lithium polysulfides in lithium-sulfur battery,however,the unsatisfactory structural stability and electrical conductivity limit the application of mesoporous MOFs(MMOFs)in Li-S batteries.Aiming at sensible solutions,the conductive polyaniline(PANI)was incorporated into the MMOF to enhance the discharge capacity and the cycling stability of proposed Li-S batteries,as the stability and the conductivity of the MMOF cathode was improved simultaneously.The activated MMOF-PANI provides physical and chemical adsorption of polysulfides against their shuttle effect.Moreover,the introduction of PANI into the channels of MMOF effectively improves the conductivity of MMOF,thus improving the electrochemical performance of the MMOF-PANI-based batteries.Benefiting from these synergetic effects,the S@MMOF-PANI cathode delivers improved electrochemical performance including excellent rate performance and cycling stability.The battery shows an initial capacity of 777.7 mAh·g^(−1)at 2.0 C and a low decay rate of 0.06%per cycle in 1,000 cycles and approximately a repeatable rate performance.
