Facile solution combustion synthesis of MoO2 nanoparticles as efficient photocatalysts

Abstract

Foam-like MoO₂ assembled from nanoparticles was fabricated by a solution combustion synthesis method using hexaammonium molybdate, ammonium nitrate (NH₄NO₃) and glycine as the precursors. The effect of the glycine/NH₄NO₃ ratio (Φ = 0.25, 0.50, 0.75, 1.0 and 1.25) on the physicochemical properties of the final products was systematically studied. The Φ value was found to display significant roles in the final phases and morphologies of the products. With a Φ value of 0.50, the foam-like product consisting of MoO₂ nanoparticles with an average size of about 20–30 nm was synthesized. The photocatalytic activities of the foam-like MoO₂ towards degradation of several contaminants, including methyl orange (MO), methylene blue (MB), rhodamine B (Rh B) and phenol, were investigated. The foam-like MoO₂ offered excellent capability and stability toward photocatalytic degradation of the studied contaminants. The results reported here demonstrated that rational design of MoO₂-based photocatalysts might be able to improve their properties in energy conversion and environmental preservation.