Abstract
LiBr as a promising redox mediator(RM)has been applied in Li-O2 batteries to improve oxygen evo-lution reaction kinetics and reduce overpotentials.However,the redox shuttle of Br3-can induce the unexpected reactions and thus cause the degradation of LiBr and the corrosion of Li anode,resulting in the poor cyclability and the low round-trip efficiency.Herein,MgBr2 is firstly employed with dual func-tions for Li-O2 batteries,which can serve as a RM and a SEI film-forming agent.The Br-is beneficial to facilitating the decomposition of Li2O2 and thus decreasing the overpotential.Additionally,a uniform SEI film containing Mg and MgO generates on Li anode surface by the in-situ spontaneous reactions of Mg2+and Li anode in an O2 environment,which can suppress the redox shuttle of Br3-and improve the inter-face stability of Li anode and electrolyte.Benefiting from these advantages,the cycle life of Li-O2 battery with MgBr2 electrolyte is significantly extended.
基金项目
国家自然科学基金(21978110)
国家自然科学基金(52171210)
Jilin Province Science and Technology Department Program(YDZJ202101ZYTS047)
Jilin Province Science and Technology Department Program(20220201130GX)
Jilin Province Science and Technology Department Program(20200201187JC)
Science and Technology Project of Jilin Provincial Education Department(JJKH20210444KJ)
NETL
NSTL
万方数据