Synthesis and Characterization of Silver Nanoparticles-Coated Molybdenum Oxide Thin Films

A thin film of molybdenum oxide was deposited employing physical vapor deposition (Thermal vacuum evaporation), and silver nanoparticles were prepared using a low-cost, safe, and environmentally friendly (non-thermal plasma) method. The structural, morphological, and optical characteristics of AgNs-coated molybdenum oxide have been described and evaluated. The X-ray diffraction results indicated that molybdenum oxide, silver oxide, and molybdenum nanoparticles crystallized in the mixed crystalline phase. The intensity of the molybdenum oxide diffraction peaks improved, and the full width at half maximum decreased, demonstrating an effect of silver nanoparticles on the structural characteristics, and the average crystallite size increased to 12.81 nm. Morphological investigation revealed that the nanostructured silver oxide layer considerably impacted the MoO3 grain size distribution, reducing it from 52 nm to 12 nm with grain boundaries of the aggregated particles. The transmittance of the molybdenum oxide film was up to 50%, but it dropped to 30% after the top layer of silver nanoparticles was deposited. The energy gaps of the uncoated and silver oxide-coated molybdenum oxide films have been estimated to be 3.66 and 3.62 eV, respectively. The developed films have shown promising properties in electronic applications, including optoelectronic devices and gas sensors.