Metal selenides as promising anode materials for potassium ion batteries(PIBs)have attracted great research attention.However,it is still a challenge to promote its practical application due to the unsatisfactory cycl...Metal selenides as promising anode materials for potassium ion batteries(PIBs)have attracted great research attention.However,it is still a challenge to promote its practical application due to the unsatisfactory cyclability resulting from large volume variation and sluggish kinetics.Herein,we tackle this issue by focusing on a promising but undemonstrated anode,bismuth selenide for PIBs which possesses a high theoretical capacity and good electronic conductivity.Benefitting from the carbon layer coating,Bi_(2)Se_(3)@C has the capability to inhibit self-aggregation and buffer the volume expansion,leading to outstanding potassium-ion storage capability.It exhibits a very high reversible capacity of 526 mA h g^(-1)at 50 mA g^(-1),as well as superior cyclability and rate capability while maintaining a high capacity of 214 mA h g^(-1)at 1.0 A g^(-1)after 1000 cycles.Furthermore,its fast and reversible ion storage mechanism was verified,which first involves conversion and subsequent alloying redox reactions.This work enriches the understanding and development of stable conversion/alloying-based anodes for high-performance potassiumion batteries.展开更多
基金supported by the National Natural Science Foundation of China(22076116)the German Research Foundation(DFG:LE2249/5-1)the Sino-German Center for Research Promotion(GZ1579).
文摘Metal selenides as promising anode materials for potassium ion batteries(PIBs)have attracted great research attention.However,it is still a challenge to promote its practical application due to the unsatisfactory cyclability resulting from large volume variation and sluggish kinetics.Herein,we tackle this issue by focusing on a promising but undemonstrated anode,bismuth selenide for PIBs which possesses a high theoretical capacity and good electronic conductivity.Benefitting from the carbon layer coating,Bi_(2)Se_(3)@C has the capability to inhibit self-aggregation and buffer the volume expansion,leading to outstanding potassium-ion storage capability.It exhibits a very high reversible capacity of 526 mA h g^(-1)at 50 mA g^(-1),as well as superior cyclability and rate capability while maintaining a high capacity of 214 mA h g^(-1)at 1.0 A g^(-1)after 1000 cycles.Furthermore,its fast and reversible ion storage mechanism was verified,which first involves conversion and subsequent alloying redox reactions.This work enriches the understanding and development of stable conversion/alloying-based anodes for high-performance potassiumion batteries.
