Effect Of Morphology Of C-Rich Silicon Carbonitride Ceramic On Electrochemical Properties Of Sulfur Cathode For Li-S Battery

Porous conducting materials represent a promising support for the immobilization of sulfur in the cathode of lithium-sulfur (Li-S) batteries. Herein, we provide an easy and scalable procedure for the preparation of such cathodes. This strategy consists of an infiltration of sulfur under solvothermal conditions at 155 degrees C into pores of carbon-rich silicon carbonitride (C-rich SiCN). Porous polymer-derived SiCN ceramics possess a unique combination of high electronic conductivity and robust, stress accommodating mechanical properties. The impact of the initial porosity and elemental composition of SiCN ceramics on the electrochemical performance of SiCN-S composites is addressed in this work. It is shown that material pyrolyzed at 10 0 0 degrees C revealing a mesoporous character in line with the presence of a free carbon phase dispersed in SiCN demonstrates the best electrochemical stability and the highest capacity (more than 310 mAh/g over 40 cycles) at a high sulphur content of 66 wt.%. (c) 2021 Elsevier Ltd. All rights reserved.