WS 2 nanosheets decorated by Ag nanoparticles with different content and uniform distribution for enhanced electrochemical properties

Abstract

A nanocomposite consisted of Ag nanoparticles and WS₂ nanosheets was prepared by a two-step procedure, in which Ag sol was generated at first, then added into WS₂ nanosheet dispersion to form the nanocomposite via self-assembly. The nanocomposites with different content of Ag nanoparticles were successfully prepared. The results show that Ag nanoparticles with the diameter of 10–20 nm are uniformly distributed on WS₂ nanosheets and not oxidized. All nanocomposites are mesoporous. The specific surface area and the mesoporosity of WS₂ are improved due to the existence of Ag nanoparticles. The specific capacitance of the nanocomposite increases with the increasing content of Ag nanoparticles. The 2000 cycles of charging and discharging were carried out on 20%AgNPs@WS₂ nanocomposite, proving its good cycling performance. It has smaller transfer resistance and internal series resistance than WS₂ nanosheets. This nanocomposite has potential application in supercapacitors.

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