Sol-gel synthesized barium doped TiO2 nanoparticles for solar photocatalytic application

Undoped and barium doped TiO2 (Ba-TiO2) nanoparticles (NPs) were prepared by facile sol-gel method. The synthesized NPs were calcined at 500 °C to change the amorphous NPs into crystalline NPs. The increased size of TiO2 NPs after Ba doping was observed from SEM and TEM analysis. The existence of Ti, O, and Ba elements in Ba-TiO2 NPs was confirmed by EDS and ICP-MS. The XRD profile exhibited the presence of anatase phase and barium titanate phase for Ba-TiO2 NPs. Specific surface area and porosity of pure TiO2 and Ba-TiO2 NPs was studied using BET surface area analyzer. The functional groups of the Ba-TiO2 NPs were identified by FTIR. The Eg of pure TiO2 and Ba-TiO2 NPs was studied by UV–Vis spectrum. From NLO studies, the pure TiO2 NPs showed higher second harmonic generation (SHG) efficiency compared to Ba-TiO2 NPs. The photocatalytic activity of pure TiO2 and Ba-TiO2 NPs was investigated towards the degradation of methylene blue (MB) dye under solar light irradiation. The mineralization of methylene blue dye was studied by TOC analyzer.