ZnS nanoparticles as the electrode materials for high-performance supercapacitors

ZnS nanoparticles electrode has been synthesized via a simple hydrothermal technique and anion exchange reaction for supercapacitor application. The as-prepared ZnS powder possesses high crystallinity and phase purity, which possesses uniform nanoparticles with an average grain size of 30-40 nm and homogeneous dispersion. The shape of cyclic voltammetry curves with different scanning rates indicates a reduced polarization effect of the ZnS nanoparticles electrode. The ZnS electrode manifests drastically superior electrochemical performance covering a supreme reversible specific capacitance of 824 F g(-1) at 1 A g(-1), outstanding rate capability of 57.7% capacitance retention even if the current density increases by 20 times, and prominent ultralong-life at large current densities of 5.0 and 10.0A g(-1). The initial specific capacitance of ZnS nanoparticle is 557F g(-1) at 10 A g(-1), and it also delivers 518.4 F g(-1) after 10,000 cycles with a high capacitance retention of 93.1%. These above results shed light on new avenues for promising electrode materials in supercapacitors.