Cerium-doped SnS micron flowers with long life and high capacity for hybrid supercapacitors

Supercapacitors with long life and high power density can be used in power tools and wind power equipment. However, increasing energy density without sacrificing advantages remains a major challenge, which limits their practical application. Therefore, efforts have been made to manufacture supercapacitors with high capacitance and long life. Ce-doped SnS micron flowers grown on nickel foam (Ce@SnS/NF) have been synthesized using a facile solvothermal method. The effect of Ce doping on the SnS, where Ce doping confined the growth of Ce@SnS to form smaller nanosheets and provided more active sites, resulting in the enhancement of the capacity and cycle stability, has been explored. In a three-electrode system, the specific capacitance increased from 1237 F/g (171.8 mAh/g) to 2549 F/g (354.0 mAh/g) at 2 A/g, and the stability was 85.5 % after 10,000 cycles at 10 A/g. A hybrid supercapacitor (Ce@SnS/NF (+)//AC (–)) assembled from Ce@SnS/NF and activated carbon as cathode and anode, respectively. The device has an energy density of 48.83 Wh/kg at 824.91 W/kg and long cycle stability (91.6 % retention after 20,000 cycles at 5 A/g). Moreover, the supercapacitor can power a white light-emitting diode (LED) for 15 min, so the Ce-doped SnS cathode has vast application prospects in supercapacitors.