Abstract
In this work, the influences of the Ar flow-rate and sublimation temperature on the phase composition and morphological structure of the sublimation products of analytical reagent MoO(3) are investigated. The results show that the sublimation products are always composed of thermodynamically stable orthorhombic molybdenum trioxide (α-MoO(3)) and metastable monoclinic molybdenum trioxide (β-MoO(3)) under different reaction conditions, among which the proportion of β-MoO(3) gradually increases with the increase in Ar flow-rate and the decrease in sublimation temperature. The formation temperature of α-MoO(3) is mainly between 780 K and 847 K, with the particles exhibiting an obvious sheet-like morphology. This work also finds that β-MoO(3) is mainly generated below 500 K; however, due to the co-actions of the deposition of gaseous MoO(3) molecules, the adsorption of Ar molecules, and the collision effect between the different particles, the newly formed β-MoO(3) is more inclined to take a spherical-shaped morphology in order to maintain its lowest energy state.