Electron beam induced transformation of MoO3 to MoO2 and a new phase MoO

The transformation of MoO3 induced by electron beam irradiation was studied by electron energy-loss spectroscopy (EELS) in combination with electron diffraction and high-resolution transmission electron microscopy (HRTEM) techniques. The routes of structure transformation were dependent on the applied electron current density. In case of low current density, MoO2 was obtained. In case of high current density, MoO with a rock-salt structure is suggested to be the final phase. The change in oxidation states of the Mo oxides was deduced from the features in energy-loss near edge structure (ELNES) of the O K-edge. Quantitative analysis was successfully employed on Mo M-3-edge and O K-edge to obtain the O/Mo ratio of the reduced phases. The mechanisms of different structure transformation behaviors were suggested in the frame of radiolysis enhanced diffusion.