Single‐Atom‐Regulated Heterostructure of Binary Nanosheets to Enable Dendrite‐Free and Kinetics‐Enhanced Li–S Batteries

Abstract

AbstractHeterostructures show potential as electrodes/functionalized separators for lithium‐sulfur (Li‐S) batteries owing to their remarkable electroactive and structural stability. Yet, the heterostructures with unique structures as well as the regulation of heterointerface electronic structure are still challenging for high‐performance Li–S batteries. Herein, Pt single‐atoms (SAs)‐regulated heterostructures of In2S3/Ti3C2 binary nanosheets (Pt SAs/In2S3/Ti3C2) are facilely constructed via an ultrasound‐assisted photochemical reduction strategy for dendrite‐free and kinetics‐enhanced Li–S batteries. The as‐designed heterostructures of Pt SAs/In2S3/Ti3C2 on separator can stabilize the Li plating/striping on Li anodes even at a high current density of 5 mA cm−2. In addition, Pt SAs/In2S3/Ti3C2 heterostructure can suppress the polysulfide shuttling and exhibit excellent redox electrocatalytic properties for lithium polysulfides decomposition. The batteries with heterostructure‐modified separators show a high initial discharge capacity of 1068.4 mAh g−1 at 0.5 C, excellent rate performances (719.6 mAh g−1 at 5C), and a remarkable cycling ability. Even with a high sulfur loading of 6.4 mg cm−2, the pouch cell can deliver an areal capacity of 5.54 mAh cm−2 at 0.2 C. This work not only provides a new route for preparing SA‐catalysts, but also sheds new lights into engineering electronic structures of heterointerfaces for developing high‐performance Li–S batteries.