Decoration of WS2 Nanotubes and Fullerene-Like MoS2 with Gold Nanoparticles

A new technique of gold nanoparticle (AuNP) growth on the sidewalls of WS2 inorganic nanotubes (INT-WS2) and the surface of MoS2 fullerene-like nanoparticles (IF-MoS2) is developed to produce metal-semiconductor nanocomposites. The coverage density and mean size of the nanoparticles are dependent on the HAuCl4/MS2 (M = W, Mo) molar ratio. AuNPs formation mechanism seems to involve spatially divided reactions of AuCl4- reduction and WS2/MoS2 oxidation taking place on the surface defects of the disulfide nanostructures rather than directly at the AuNP-INT/IF interface. A strong epitaxial matching between the lattices of the gold nanoparticles and the INT-WS2 or IF-MoS2 seems to suppress plasmon resonance in the nanocomposites with small (<10 nm mean size) AuNPs.