Electrochemical deposition of quantized particle MoS2 thin films

Thin films of uniform MoS2 nanoparticles smaller than 10 nm, were produced by electrochemical deposition on conducting glass from nonaqueous solutions of (NH4)(2)MoS4 in ethylene glycol. The as-deposited films were x-ray amorphous with a composition determined by electron probe microanalysis close to MoS2. Transmission electron microscopy, selected area diffraction, and high resolution electron microscopy (HREM) showed that the particles are hexagonal 2H-MoS2 having a size distribution ranging from 3 to 10 nm. HREM showed clearly that the nanoparticles had flat facets and that they were deposited with their van der Waals (002) basal planes perpendicular to the substrate surface (type I texture) exhibiting the (100) and (110) edge planes to the surface. Optical studies revealed size quantization effects in their optical absorption spectra.