Solar-based Photocatalytic Degradation of Wastewater by Vanadium-doped CaTiO₃ Nanoparticles

Calcium titanate (CaTiO₃), a member of the perovskite family, is a multifunctional material with a wide range of uses, including photocatalytic wastewater treatment, electronic devices, lighting and display devices, biomedicine and many more. In this work, for the first time, the CaTiO₃ nanoparticles (NPs) doped with different molar (0.2, 0.4, 0.6, and 0.8) percentages of Vanadium (V) were successfully synthesized via a Sol–gel method and used for the photocatalytic treatment of a wide range of wastewater. It is interesting to note that even after doping vanadium, the CaTiO₃ crystal structure retained its perovskite structure, and the V-doped CaTiO₃ displayed increased solar or visible light absorption with a band gap from 1.96 to 2.34 eV. Studies were conducted using XRD for phase formation, FESEM for morphology, EDX for structural composition, and UV–Vis for band gap. The percentage of Chemical Oxygen Demand (COD) removal was examined under sunlight at various irradiation times ranging from 2 to 8 h with a catalyst dose of 1 g/L and pH of 7.2 to examine the impact of Vanadium doping on the photocatalytic performance of CaTiO₃. The percentage of COD removal from sewage treatment plant effluent, textile industry effluent, and landfill leachate was 98%, 94%, and 88% respectively using 0.4 mol% of V-doped CaTiO₃.