Heterogenization-Activated Zinc Telluride via Rectifying Interfacial Contact to Afford Synergistic Confinement-Adsorption-Catalysis for High-Performance Lithium-Sulfur Batteries.

ABSTRACT

The notorious shuttle effect and sluggish conversion kinetics of intermediate polysulfides (Li2S4, Li2S6, Li2S8) are severely hindered the large-scale development of Lithium-sulfur (Li-S) batteries. Rectifying interface effect has been a solution to regulate the electron distribution of catalysts via interfacial charge exchange. Herein, a ZnTe-ZnO heterojunction encapsulated in nitrogen-doped hierarchical porous carbon (ZnTe-O@NC) derived from metal-organic framework is fabricated. Theoretical calculations and experiments prove that the built-in electric field constructed at ZnTe-ZnO heterojunction via the rectifying interface contact, thus promoting the charge transfer as well as enhancing adsorption and conversion kinetics toward polysulfides, thereby stimulating the catalytic activity of the ZnTe. Meanwhile, the nitrogen-doped hierarchical porous carbon acts as confinement substrate also enables fast electrons/ions transport, combining with ZnTe-ZnO heterojunction realize a synergistic confinement-adsorption-catalysis toward polysulfides. As a result, the Li-S batteries with S/ZnTe-O@NC electrodes exhibit an impressive rate capability (639.7 mAh g-1 at 3 C) and cycling performance (70% capacity retention at 1 C over 500 cycles). Even with a high sulfur loading, it still delivers a superior electrochemical performance. This work provides a novel perspective on designing highly catalytic materials to achieve synergistic confinement-adsorption-catalysis for high-performance Li-S batteries.