Engineering Defect-Rich Bimetallic Telluride with Dense Heterointerfaces for High-Performance Lithium-Sulfur Batteries

Rechargeable lithium-sulfur (Li-S) batteries have received ever-increasing attention owing to their ultrahigh theoretical energy density, low cost, and environmental friendliness. However, their practical application is critically plagued by the sluggish reaction kinetics, shuttling of soluble polysulfide intermediates, and uncontrollable growth of Li dendrites. Herein, a bimetallic telluride electrocatalyst with dense heterointerfaces and rich defects embedded in hollow carbon polyhedron bunches (N subset of CoTe1-x/ZnTe1-y@NC, abbreviated as NCZTC) is rationally designed to simultaneously address the S cathode and Li anode problems. Both experimental and computational results substitute the integration of dense heterointerfaces and rich defects can synergistically modulate the electronic structure, enhance the electrical conductivity, promote the Li+ transportation, strengthen the polysulfides adsorption and improve the catalytic activity, thereby significantly accelerating the redox conversion kinetics and prevent the dendrite growth. Consequently, Li-S batteries with NCZTC-modified separators demonstrate excellent electrochemical performance including high specific discharge capacity, remarkable rate capability, good long-term cycling stability, and competitive areal capacity even at high sulfur loading and lean electrolyte conditions. This study not only provides valuable guidance for designing efficient sulfur electrocatalysts with transition metal tellurides but also emphasizes the importance of heterostructure design and defect engineering for high-performance Li-S batteries. The high-efficiency N subset of CoTe1-x/ZnTe1-y@NC electrocatalyst is rationally designed for Li-S batteries. Both experimental and theoretical results substantiate that the integration of dense heterointerfaces and rich defects (Te vacancy-induced N-doping) can synergistically accelerate the sulfur conversion and protect the lithium anode from corrosion. This study provides an innovative strategy for constructing high-performance sulfur electrocatalysts with transition metal tellurides. image