Ce-doped ZnO as photocatalyst for carbamazepine degradation

Abstract

Cerium-doped zinc oxide (CeZnO) materials were synthesized at pH 4 and 8 using zinc acetate as precursor. The synthesized catalysts were characterized by Raman, Fourier transform infrared spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy. Their photocatalytic activity was evaluated using visible light irradiation and an emerging pollutant, carbamazepine. Characterization results showed that the catalyst obtained at pH 8 presented two crystalline phases corresponding to ZnO and CeO2. However, no crystalline phase of wurtzite was found for the catalyst synthesized at pH 4. Besides, doped material spectroscopies indicated ZnO lattice distortion and perturbation of the Zn–O–Zn network, which are characteristic of structures where cerium is incorporated in the crystalline structure of zinc oxide. The CeZnO catalyst synthesized at pH 8 showed higher photocatalytic performance than the material synthesized at pH 4. With the former, 53 % of carbamazepine could be removed within 180 min under visible light irradiation. In addition, photodissolution of ZnO from the solid particles decreased for doped samples in comparison with the undoped one.