Facile one-pot synthesis of Bi2S3 nanorod @ N, S co-doped carbon composite for high performance lithium ion batteries

Abstract

Bismuth sulfide is favoured in lithium ion batteries due to its high specific capacity of 625 mAh/g. However, the Bi₂S₃ anode faces severe volume expansion problems during the lithium intercalation process, resulting in continuous electrode fragmentation and rapid degradation of lithium storage performance. In this study, Bi₂S₃ nanorod@N, S co-doped carbon composite prepared by a simple sintering method was used as the anode material for lithium ion batteries. 1D Bi₂S₃ nanorods with a length of 1 μm and a diameter of 50 nm were loaded in situ on 2D N, S co-doped carbon nanosheets. This unique structure can not only alleviate the volume change of bismuth sulfide, but also effectively shorten the diffusion distance of lithium ions, thereby improving the cycling stability and rate capability at the same time. The discharge capacity of Bi₂S₃@N, SC remained at 583.4 mAh g ^–1 after 400 cycles at 0.5 A g^–1. Even at a high current density of 2 A/g, the discharge capacity of Bi₂S₃@N, SC still reached 374.3 mAh g ^–1. This simple method also can be extended to the preparation of other metal sulfide composites.