Synthesis, characterization, and photodegradation assessment of Ni and Cd-doped TiO2 nanocrystals via sol-gel method for methylene blue under sunlight

Abstract

Pristine TiO2, Ni-doped, and Cd-doped TiO2 nanocrystals were successfully synthesized by utilizing a single-step sol-gel process. The average particle size (D) of pristine TiO2 was found to be 10.64 nm, while with the addition of Cd and Ni content (0.1) w%, the crystallite size steadily dropped to (10.39 to 8.44) nm. The band gap energies of (0.1) w% Cd and nickel-doped TiO2 are determined (3.20 and 3.07) eV, respectively, which are smaller than that of 3.29 eV for the pristine TiO2. The assessment of the photosensitive activity under visible light irradiation was conducted using the Methylene blue (MB) degradation rate.