One-step synthesis of SnS₂/SnO₂ nanoflowers for high-performance hybrid supercapacitors

In this work, the flower-like SnS2/SnO2 (nanoflowers, NFs) composite and SnS2 nanosheets (NSs) were respectively prepared in the presence of different amount of thiourea through a facile one-step hydrothermal method. These SnS2/SnO2 NFs and SnS2 NSs exhibited the typical battery-like electrochemical response. At the current load of 1 A g(-1), the specific capacity was determined to be 304.6 C g(-1) for NFs composite and 244.1 C g(-1) for NSs. In order to evaluate the potential of practical application in electrochemical energy storage, a hybrid supercapacitor (HSC) was assembled with these SnS2-based electrode materials as cathode and activated carbon (AC) as anode, and the HSC could be operated over a maximum voltage of 1.6 V. The SnS2/SnO2 NFs//AC HSC delivered an energy density of 33.4 W h kg(-1) at the power density of 993.2 W kg(-1). In contrast, the SnS2 NSs//AC HSC exhibited 27.4 W h kg(-1) at 929.9 W kg(-1). Both HSCs showed good cycling performance during the continuous 5000 GCD cycles without any capacity decay. This impressive electrochemical property proves that the SnS2/SnO2 NFs composite can serve as promising electrode material for the assembly of advanced HSC device. In addition, the present synthetic strategy can be extended to the synthesis of other transition metal sulfides (TMSs)-based electrode materials with controllable shapes and excellent electrochemical response.