1 Visible Light Active Nitrogen and Cobalt Doped TiO2 Nanoparticles: Synthesis, Characterization and Photocatalytic Activity , Aroosa Javed*, Memoona Qammar, Rooha Khurram, Zaib-Un-Nisa
TiO2 and different variants of nitrogen and cobalt co-doped TiO2 (CoN-TiO2) catalysts is reported in this study to utilize visible light efficiently in photocatalysis. Catalysts were successfully synthesized by employing the sol-gel method and crystalline phase analysis was carried out via X-ray Diffraction (XRD) which confirmed the formation of anatase phase with tetragonal structure. The spherical morphology and uniform size distribution in the range of 20-40 nm were validated by Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDX). While Diffused Reflectance Spectroscopy (DRS) was deployed for the study of optical properties and decrease in bandgap from 3.2 eV for pristine TiO2 to 2.34 for 8 wt. % N, Co co-doped TiO2 was observed. The photocatalytic activity of pure TiO2 and Co-N doped TiO2 nanoparticles was studied against methyl orange and performance jumped from 32% for undoped to 80% for 8 wt. % N,Co co-doped TiO2 that can be attributed to decreased bandgap and uniform size distribution.