Cooperative Co Single Atoms and Co2P Nanoparticles as Catalytic Tandem for Boosting Redox Kinetics in Li–S Batteries

Abstract

Notorious shuttle effect and sluggish redox kinetics as major bottlenecks have nowadays hindered the commercial implementation of lithium–sulfur batteries. The activity design of catalysts has attracted increasing attention in this realm thus far. Herein, we devise a Co-based electrocatalytic tandem (Co–N–P) encompassing (N,P)-coordinated Co single atoms and Co₂P nanoparticles for guiding the dual-directional sulfur evolution reactions. Such a Co–N–P tandem synergizes high atom utilization, large catalyst loading and smooth charge migration, thereby resulting in the high activity for dictating the Li₂S nucleation and decomposition. As a result, the full cell incorporating the Co–N–P modified separator harvests 0.1% capacity decay after 500 cycles at 1.0 C. In addition, a favorable areal capacity output of 4.2 mAh cm^–2 is obtained under a sulfur loading of 5.3 mg cm^–2. We anticipate that this work would offer insight into the hybrid catalyst design affording high activity and stability for emerging energy applications.