Synthesis of molybdenum oxide nanoparticles by nanosecond laser ablation

Abstract

Molybdenum oxides (MoOx) nanoparticles (NPs) have great optical and electronic features that make them suitable for potential applications such as surface enhanced Raman spectroscopy (SERS) and energy systems. However, there are very few papers that report the synthesis of MoOx NPs by using the laser ablation of solids in liquids (LASL) technique and they lack the explanation for the oxidation process. This work reports on the generation of NPs composed of molybdenum trioxide hydrated (MoO3 $ xH2O) (x ¼ 1, 2) by using this method and its oxidation due to aging. A picosecond Nd:YAG laser was used and the per pulse laser fluence was varied from 5 to 20 J/cm2. Spherical NPs were obtained with average diameters from 48 to 141 nm, respectively. The absorption evolution of the obtained colloids was characterized by optical absorption spectroscopy, TEM was used to study the MoOx NPs morphology, size and structure and Raman spectroscopy to determine the material chemical composition.