二维超晶格氧化钛基功能隔膜层的制备及锂硫电池性能研究OA

Lithium-sulfur ﹙Li-S)batteries are regarded as highly promising large-scale energy storage devices due to their high energy density.However,severe shuttle effects and sluggish conversion kinetics of lithium polysulfides significantly hinder their practical application.Here,two-dimensional monolayer lepidocrocite-type titanium dioxide ﹙Ti0.87O2)nanosheets with titani-um vacancies were synthesized and alternately stacked with graphene monolayers to construct a Ti0.87O2/rGO superlattice structure.Experimental results demonstrate that the rGO framework significantly enhances the electrical conductivity of the material,while the Ti vacancies endow Ti0.87O2 with higher surface acidity,thereby strengthening its chemical adsorption capability toward LiPSs.When employed as a modified layer coating on separator surfaces,the Ti0.87O2/rGO superlattice remarkably accelerates the redox re-action kinetics of the sulfur electrodes and facilitates efficient catalytic conversion of LiPSs.Compared with traditional Li-S batter-ies,this architecture delivers a high discharge capacity of 944 mAh•g-1 at 0.2 C and exhibits an ultralow capacity decay rate of only 0.080%per cycle over 200 cycles at 1 C.This synergy-driven strategy provides a new path for developing high-performance Li-S batteries.