Photoluminescence and photocatalytic activity of spin coated Ag+ doped anatase TiO2 thin films

Ag + doped TiO2 (Ag-TiO2) thin films were coated on glass substrates with different dopant concentrations (1%, 3%, 5% 7% and 10%) and were subsequently annealed at 550 degrees C. The crystalline structure and phase formation of Ag-TiO2 was examined using XRD. The HRTEM analysis of pure and 5% Ag doped TiO2 thin films was revealed that the particles are spherical in shape with sizes around 23.8 and 11.6 nm respectively. Raman spectrometer was also used to identify the phase formation and vibrational modes present in the prepared silver doped TiO2 coatings. EPR spectra confirm the presence of oxygen vacancies (Vo) and Ti3+ sites in the Ag-TiO2 thin films. With excitation at 325 nm, Ag doped TiO2 nanoparticles show characteristic photoluminescence (PL) corresponding to the visible spectral range. Ag doped TiO2 thin films showed enhanced photocatalytic behaviour due to their narrow band gap energy (3.17-2.75 eV), high surface area (85-231 m(2)/g), and a reduced luminescence. Among all the films 5% Ag-TiO2 film exhibited strong photocatalytic activity (PCA) and was estimated by visible light decolorization of methylene blue (MB) and methyl orange (MO).