Synthesis of Ni doped-TiO2 Thin Film Photocatalysts on Glass Surfaces

Abstract

Thin film of TiO₂ modified Ni²⁺ cationic (Ni doped-TiO₂) thin films were synthesized from titanium tetraisopropoxide (TTIP) and Ni(NO₃)2.6H₂O using the combined sol-gel and dip coating method followed by calcination at 500^oC for an hour. This study aims to determine the concentration of Ni²⁺ and the optimum number of layers for application as self-cleaning. Frontier transform infrared (FTIR) spectrophotometric analysis observed a shift in the vibration absorption peak of Ti-O towards a smaller wave number as an indication that the Ni²⁺ cationic have incorporated in the TiO₂matrix in forming Ni-TiO₂. Based on the of x-ray diffraction (XRD) it is known that Ni-TiO₂ has anatase crystalline phase with a crystallite size of 149.20 nm. Diffuse reflectance ultraviolet-visible (DRSUV-Vis) spectrophotometry showed a decrease in the bandgap energy (3.2 eV to 2.22 eV). Surface morphological by scanning electron microscopy (SEM) method showed that the addition of polyethylene glycol (PEG) resulted in a more homogeneous distribution of particles than thin films without PEG. The self-cleaning activity of Ni-TiO₂ was tested for surface hydrophilic properties by measuring the contact angle of water and oil droplets under visible light illumination.