Flower-like structure of SnS with N-doped carbon via polymer additive for lithium-ion battery and sodium-ion battery

In this work, flower-like SnS with N-doped carbon is synthesized by two steps including hydrothermal method and sintering at moderate temperature in a protective atmosphere. Initially, the morphology is controlled into flower-like particles in the hydrothermal method after the adding of Polyvinylpyrrolidone. The flower-like particles form a large surface area and shorten the diffusion path of ions to transfer. In addition, Polyvinylpyrrolidone is also regarded as a carbon source. After pyrolysis of Polyvinylpyrrolidone, C-N structure is easily obtained to promote the electrochemical performance in high current density. In electrochemical performance, the flower-like SnS containing N-doped carbon displays a high capacity of 1047 mAh/g after 30th cycles and around 826 mAh/g after 50th cycles at 100 mA/g in lithium-ion battery. Moreover, the impedance also decreases significantly. It is demonstrated that the Polyvinylpyrrolidone plays a vital role controlling the structure of SnS into flower-like powder and producing a perfect net for diffusion path. It is anticipated that SnS is a potential material for tin-based anode due to the higher conductivity and 2-Dimensional structure. Such facile method offer the functions including not only controlling the morphology and doping N-doped carbon.