Black BaTiO3 as multifunctional sulfur immobilizer for superior lithium sulfur batteries

Lithium sulfur (Li-S) batteries are highly promising next-generation energy-storage technology due to their high energy density, low cost and environmental benignity. However, concerns are fueled regarding the detrimental shuttle effect of the intermediate polysulfide and the insulting nature of sulfur as they severely restrict the practical performance. Herein, a unique “black” BaTiO3 (B-BTO) was developed for the first time as a multi-functional sulfur immobilizer for improving the Li-S battery performance. The high conductivity of B-BTO expedites the electron transfer and facilitates the sulfur reaction kinetics, while the intrinsic ferroelectricity of B-BTO and the chemical interactions between B-BTO and polysulfide electrostatically and chemically confine the sulfur species, respectively. Attributed to these superiorities, the B-BTO-based sulfur electrode achieves efficient inhibition on shuttle effect and significantly improved performance. This work presents a novel and highly effective strategy in improving the sulfur electrochemistry as well as promoting the future implementation of Li-S batteries.