Single-Atom Cobalt Supported on Nitrogen-Doped Three-Dimensional Carbon Facilitating Polysulfide Conversion in Lithium–Sulfur Batteries
Yichen Wang, Chunsheng Shi, Junwei Sha, Liying Ma, Enzuo Liu, Naiqin Zhao
Abstract
Single-atom catalysts (SACs) have demonstrated catalytic efficacy toward lithium polysulfide conversion in Li–S batteries. However, achieving high-density M–Nx sites with rational design by a simple method is still challenging to date. Herein, an ultrathin porous 3D carbon-supported single-atom catalyst (SACo/NDC) is synthesized with a salt-template strategy via a facile freeze-drying and one-step pyrolysis procedure and serves well as a sulfur host. The well-defined 3D carbon structure can effectively alleviate volume stress and confine polysulfides inside. Moreover, the dispersed Co–Nx sites exhibit strong chemical adsorption function and valid catalytic efficiency to LiPSs redox conversion. As a result, the SACo/NDC cathodes display enhanced long-term cycling stability and better rate capability.