Manipulating the Redox Kinetics of Li–S Chemistry by Tellurium Doping for Improved Li–S Batteries

Abstract

Fundamentally altering the essential properties of a material itself is always of great interest but challenging as well. Herein, we demonstrate a simple tellurium doping method to intrinsically reshape the electronic properties of the sulfur and manipulate the kinetics of Li–S chemistry for improving the performance of Li–S batteries. DFT calculation indicates that Te doping can effectively facilitate the lithiation/delithiation reactions and lower the lithium ion diffusion energy barrier in Li2S. Additionally, electrochemical studies prove that the reaction kinetics of Li–S chemistry and cycling performance of Li–S batteries have been significantly improved with Te dopants. An exceptional specific capacity of ∼656 mA h g–1 and a high Coulombic efficiency of ∼99% have been achieved at 5 A g–1 even after 1000 cycles. More importantly, the capability to manipulate the intrinsic properties of materials and explore the synergistic effects between conventional strategies and element doping provides new avenue...