Preparation of molybdenum oxide and tungsten oxide nanoparticles by pulsed laser ablation

Laser ablation synthesis in a liquid environment is a green and low-cost technique that allows the preparation of nanostructures. In the last few decades, transition metal oxide nanostructures have attracted a great deal of attention from the research community due to their diversified applications. Tungsten and molybdenum oxides have tunable bandgaps and localized surface plasmon resonance peaks in the near-infrared region in reduced form, making them promising candidates for optical sensing, optical transistors, photothermal therapy, and photocatalysis. In this work, tungsten and molybdenum oxide nanoparticles are prepared in deionized water using pure tungsten and molybdenum metal sheets. XRD results showed the formation of tungsten and molybdenum oxide. SEM images showed that particles are spherical and have different sizes. X-ray photoelectron spectroscopy results showed that the W⁺⁵ and Mo⁺⁵ oxidation states are present along with the W⁺⁶ and Mo⁺⁶ oxidation states, respectively, which indicate that the prepared WO₃ and MoO₃ oxides exist in reduced form.