Influence of Ho Substitution on Structural, Morphological, and Optical Properties of Anatase Ti1-xHoxO2 (x= 0.0, 0.01, 0.02, 0.03) Thin Films

Abstract

Ti1-xHoxO2 (x= 0.0, 0.01, 0.02, 0.03) thin films are synthesized by a sol-gel method and deposited by a dip-coating technique on the glass substrates. The films’ crystal structures are examined by an X-ray diffraction technique, while the morphological properties are investigated by scanning electron microscopy and atomic force microscopy. UV-Vis and photoluminescence spectrophotometry are used to analyze the optical properties. Based on the X-ray diffraction patterns, all the films belong to the anatase phase. It is observed that the surface characteristics, such as the morphology, film thickness, and roughness change significantly with the holmium substitution. The optical investigations reveal that the transmittance, band gap energies, and luminescence properties can be adjusted by the holmium substitution. According to the current study, holmium substituted TiO2 thin films with improved optical properties may be a suitable candidate for applications that require a wide band gap and high optical transparency as well as luminescence properties.