Metal-organomecapto complex-derived mesoporous Co1-xS/N,S-codoped carbon composite for superior lithium ion storage

Cobalt sulfide-based electrode materials were believed to have bright future in lithium-ion batteries (LIBs) application for their high theoretical capacity and excellent electrochemical stability. However, their relatively low electronic conductivity and the large volume variation during lithiation/delithiation processes usually result in low rate capability and short cycling life. Herein, a novel mesoporous Co1-xS/N,S-codoped carbon (Co1-xS/N,S–C) composite was prepared by direct pyrolysis of a cobalt-2-mercaptobenzothiazole (CoMBT) complex. High-content (91.14 ​wt%) and ultrafine (∼10 ​nm) Co1-xS nanocrystals were in-situ generated and composited with high conductive N,S-codoped carbon. The Co1-xS/N,S–C demonstrates superior Li+-ion storage performance, delivering high discharge capacities of 1207 ​mAh g−1 at 200 ​mA ​g−1 after 50 cycles and 425 ​mAh g−1 at 5 ​A ​g−1 after 1000 cycles.