Sodium and potassium ion batteries have attracted considerable attention in the last few years owing to abundant resources of sodium and potassium compared to those of lithium.Transition metal dichalcogenide MoSe_(2)s...Sodium and potassium ion batteries have attracted considerable attention in the last few years owing to abundant resources of sodium and potassium compared to those of lithium.Transition metal dichalcogenide MoSe_(2)shows great potential as an anode because of its high achievable capacity.However,the sluggish kinetics,large volume expansion and pulverization of MoSe_(2)result in severe decay of sodium or potassium storage performance.In this work,a hierarchical MoSe_(2)/N–C nanorod is synthesized with expanded interlayer spacing.Ethylenediamine(EDA)in MoO_(3)·EDA precursor plays an important role in obtaining the hierarchical nanorod structure.The insertion of C and N into the interlayer of the MoSe_(2)results in the enlarged interlayer spacing,which is derived from the carbonization of EDA.The expanded d-spacing of(002)planes enhances the diffusion kinetics of Na^(+)and K^(+)ions.The hierarchical structure and the N-doped carbon coating buffer the volume expansion during the charging/discharging process maintaining the structural integrity of MoSe_(2).As a result,MoSe_(2)/N–C exhibits long cycle performance and high rate capability for both sodium and potassium storage.展开更多
基金supported by the Jiangsu Province Natural Science Research of Universities(No.19KJB150025 and 20KJB150007)the Applied Basic Research Programs of Changzhou(No.CJ20200034)+1 种基金Jiangsu Province Innovative and Entrepreneurial Doctor Project(No.KYQ19021 and KYQ19019)Graduate Student Innovation Training Program(No.XSJCX20_13).
文摘Sodium and potassium ion batteries have attracted considerable attention in the last few years owing to abundant resources of sodium and potassium compared to those of lithium.Transition metal dichalcogenide MoSe_(2)shows great potential as an anode because of its high achievable capacity.However,the sluggish kinetics,large volume expansion and pulverization of MoSe_(2)result in severe decay of sodium or potassium storage performance.In this work,a hierarchical MoSe_(2)/N–C nanorod is synthesized with expanded interlayer spacing.Ethylenediamine(EDA)in MoO_(3)·EDA precursor plays an important role in obtaining the hierarchical nanorod structure.The insertion of C and N into the interlayer of the MoSe_(2)results in the enlarged interlayer spacing,which is derived from the carbonization of EDA.The expanded d-spacing of(002)planes enhances the diffusion kinetics of Na^(+)and K^(+)ions.The hierarchical structure and the N-doped carbon coating buffer the volume expansion during the charging/discharging process maintaining the structural integrity of MoSe_(2).As a result,MoSe_(2)/N–C exhibits long cycle performance and high rate capability for both sodium and potassium storage.
