Abstract
Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friend-liness,and low production cost.However,the low elec-tronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial devel-opment of LSBs.To solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe2-NC@ZnSe-NC).The FeSe2-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb LiPSs.At the same time,it also effec-tively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction processes.The mechanism involved in FeSe2-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)calculations.The electrochemical test results indicate that LSB with S/FeSe2-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g-1 at 0.2C.And after 500 cycles at 1C,the capacity decay rate per cycle is 0.031％,and the capacity retention rate is 85％.The FeSe2-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.
基金项目
国家自然科学基金(52130101)
Project of Science and Technology Development Plan of Jilin Province in China(20210402058GH)
Project of Science and Technology Development Plan of Jilin Province in China(20220201114GX)
NETL
NSTL
万方数据