Uniform growth of ZnS nanoflakes for high-performance supercapacitor applications

The cost-effective, efficient, and straightforward synthesis of materials for supercapacitor applications has attracted considerable attention for practical applications. In this study, thin zinc sulfide (ZnS) nanoflakes were grown on nickel foam by a facile single-step hydrothermal method. The resulting ZnS electrode delivered a high specific capacity of 659 C g–1 at 2 A g–1 and excellent cycling stability. It could function as a positive electrode in KOH electrolyte for high-performance supercapacitors. The device exhibited a remarkable specific capacity of 154 C g–1, high specific energy of 30 Wh kg–1, high specific power of 14 kW kg–1, and only a 4% decrease in the capacitance retention over 2000 cycles. Additionally, two serially connected asymmetric supercapacitor devices powered 52 red light-emitting diodes connected closely with 100 s.