Ni, Co and Mn doped SnS2-graphene aerogels for supercapacitors

Ni, Co, Mn doped SnS2-graphene aerogel (M-SnS2-GA) supercapacitor materials were synthesized by solvothermal method using metal chlorides and thioacetamide as precursors. The obtained samples formed complex 3D network structures of 2D nanosheets-graphene aerogels as the scanning electron microscopy images indicated. According to the electrochemical tests, the existence of graphene aerogel and doped metal ions fundamentally improved the electrochemical performance of SnS2. Mn-SnS2-GA exhibited the highest specific capacitance among them (523.51 F g−1 at the scan rate of 5 mV s−1), which is almost three times as high as that of SnS2 (171.56 F g−1). Meanwhile, Mn-SnS2-GA also showed excellent stability in cycling test (98.57% retention after 2000 cycles at 10 A/g). The effects of the structure and doping on the performance of the composites were deeply investigated. In addition, a symmetric supercapacitor device was also assembled and tested to confirm the application prospects.