Effect of N<SUB align="right">2 plasma treatment on TiO<SUB align="right">2 thin films for photocatalysis application

TiO2 thin films were prepared via a spin-coating technique and subsequently treated with nitrogen plasma discharge at varying gas pressures.X-ray diffraction analysis revealed characteristic peaks of the TiO2 anatase phase.Atomic force microscopy (AFM) analysis demonstrated uniformly smooth surface profiles, with an increase in the sharpness of surface features following N2 plasma treatment.UV-visible analysis indicated high transparency levels within the range of 80%-90%.Moreover, an incremental flow of nitrogen gas led to a slight reduction in the energy band gap from 3.4 to 3.2 eV.Photoluminescence emissions were detected, attributed to intrinsic emission and surface defect states.The nitrogen plasma treatment also resulted in a reduction in electrical sheet resistivity from 35 to 17 .Contact angle measurements confirmed the super-hydrophilicity of the nitrogen plasma-treated TiO2 thin films.Furthermore, the impact on the photocatalytic activity of the treated TiO2 films was found to be minimal.