Enhanced visible light-driven photocatalytic performance of Zr doped CeO₂ nanoparticles

In this study, pristine and Zr-doped CeO₂ nanoparticles with chemical formula Ce_1−xZr_xO₂ (x = 0, 0.05, 0.075 and 0.1) have been prepared through facile hydrothermal process. The influence of Zr doping on the microstructure, thermal, optical and photocatalytic properties of CeO₂ was systematically explored through various analytical techniques. Analysis of the XRD data reveals cubic fluorite structure of the samples with average crystallite size of 12, 15, 21 and 30 nm respectively for different Zr doping. The optical properties of the nanoparticles were studied through UV–visible absorption and photoluminescence (PL) spectroscopy. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy measurements were performed to examine the chemical state and microstructure of the synthesized materials. The functional groups and mode of vibrations have been identified by the Fourier transform infrared (FTIR) spectroscopy. A reduction in the optical band gap of CeO₂ (from 3.25 to 3.10 eV) is observed on systematic Zr doping. In addition, significant enhancement in the photocatalytic performance is also noticed for the doped samples (92.2%) as compared to the pristine one (68.7%) for the degradation of methylene blue (MB) dye under visible light irradiation.