Synthesis of h- andα-MoO3by Refluxing and Calcination Combination: Phase and Morphology Transformation, Photocatalysis, and Photosensitization

Abstract

Hexagonal molybdenum oxide (h-MoO3) nano- and microrods were successfully synthesized by refluxing of (NH4)6Mo7O24·4H2O solutions with the pH 1 at 90°C for 1, 3, 5, and 7 h and were further transformed into orthorhombic molybdenum oxide (α-MoO3) microplates by calcination at 450°C for 6 h. These selected products were used to determine the degradation of methylene blue dye under 35 W xenon lamp for 0–180 min, due to the photocatalysis and photosensitization processes. In this research, catalytic activity of the metastable h-MoO3has higher efficiency than that of the thermodynamically stableα-MoO3. Their phase and morphology transformation was also explained according to the experimental results.