A Study on MoS2 Thin Films Electrochemically Deposited in Ethylene Glycol at 165℃

摘要

The electrosynthesis of nanoparticle thin films ofMoS2 from solutions of (NH4)2MoS4 in ethylene glycol at 165℃,is described. The as-deposited MoS2 thin films (~150 nmthick) were X-ray amorphous and exhibited featureless opticalabsorption spectra over the 1-3.5 eV spectral range. Highresolution transmission electron microscopy (HRTEM) revealedthe presence of single or double (0002) plane-size 2H-MoS2 thinnanoplatelets (~2-3 nm) embedded in an amorphous matrix.Annealing the as-deposited samples under Ar for 1 h at 550℃,resolved a broad and weak-intensity peak in the respective X-rayspectra, identified as the (0002) Bragg peak of the bulk 2H-MoS2polytype, as well a some spectral features in the opticalabsorption spectra. HRTEM images disclose generation of avariety of nanostructures, consisting of 2-5 2H-MoS2 (0002)planes stacks (some bent) together with few polyhedralnanostructures with triangular or rectangular projections. Anappraisal of the factors influencing the reaction mechanism of thevarious MoS2 nanostructures formation is proposed.