Effect of calcination process on the gas phase photodegradation by CuO-Cu2O/TiO2 nanocomposite photocatalyst

Abstract

A series of CuO-Cu₂O/TiO₂ nanocomposite samples were prepared by the sol-gel method. Before applying the sol-gel method, the Cu(OH)₂ nanostructure on Cu powders were formed by in-situ solution treatment. The samples were characterized through some techniques and the photocatalytic performance of CuO-Cu₂O/TiO₂ nanocomposites for gas-phase 2-propanol photo-oxidation under UV and sunlight type illumination was evaluated. The effect of calcination process on the synthesis and photocatalytic activity of the samples was studied. The calcination process plays an important role in improving the properties of nanocomposite powders. The results showed that the nanocomposite formed successfully in desirable structure and morphology. The nanocomposite is composed by the mixture of TiO₂ particle with an average particle size of about 300 nm and the copper oxide nanorods with a diameter of 50-100 nm. In this nanocomposite, the copper oxides nanostructures and TiO₂ particles are the main components to form the heterojunction structure and provide enhanced photocatalytic performance compared to the TiO₂ sample. The reaction rate of the most active nanocomposite sample prepared at the optimum conditions is almost 6 times larger than the TiO₂ references.