Structural, Optical and Microstructural Properties of TiNi Thin Films before and after Oxidation

Abstract

The deposition of composites with tailored optical properties is investigated. This would employ structures consisting of combined metallic and oxides nature. A thin layer of TiNi is obtained by using RF magnetron sputtering on a stainless-steel substrate, followed by oxidation at 400°C and 800°C for four and one hours, respectively. The optical properties of the thin films were characterized by optical spectrophotometer, and Fourier Transform Infrared Spectroscopy (FTIR). The morphology, topography, and structure were studied by scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD). The results show that TiO2 has been produced through the oxidation process of the sputter-deposited TiNi thin film at high oxidation temperature. The TiNi thin films showed a significant improvement in optical properties after oxidation, as the absorbance increased, and the emittance was reduced. This work introduces oxidized TiNi thin films as candidates for solar selective absorber.