The investigation of optical and photocatalytic properties in Dy2M2O7 (M= Hf, Zr and Ce )

Abstract

This paper aims to present a group of compounds Dy2M2O7 (with M = Hf, Ce and Zr) which could be an alternative having the same function as TiO2. Based on our studies and those reported in the literature, we will discuss in detail the roles and the functional mechanism of the catalysts. The results show that Zr2Dy2O7 is the best candidate to be a photo-catalyst: it has a band gap close to 2.2 eV, and a good absorption in visible range compared to the other compound having absorption in UV. The quantum efficiency of Zr2Dy2O7   reaches up to 3%, and the limit of conduction band and valence band are localized in potential redox zone. Doping with Cerium gives another energy level, which allows having other optical transitions and improving the absorption and reaching the quantum efficiency to 4% in a visible range.