A Novel Polymer-Assisted Hydrothermal Approach to Metal-Oxide Thin Films

A Novel Polymer-Assisted Hydrothermal Approach to Metal-Oxide Thin Films

Qianglu Lin, Yun Xu, Ling Fei, Joshua Hill, Shuguang Deng, Hongmei Luo

Department of Chemical Engineering, New Mexico State University, Las Cruces, NM88003

Metal-oxide thin films exhibit a wide range of electronic, magnetic, optical, and thermal properties that conventional metallic elements and semiconductors do not possess. Numerous methods like molecular beam epitaxy, sputtering, pulsed-laser deposition, sol-gel, and polymer-assisted deposition have been used to deposit epitaxial oxide films. Crystalline anatase or rutile titanium dioxide (TiO₂) have low band gap (3.2 eV), high photocatalytic activity, and good bioactivity. We will report epitaxial anatase TiO₂ and rutile TiO₂ films on (001) LaAlO₃ and R-cut sapphire prepared by a novel chemical solution approach, polymer-assisted hydrothermal method. It provides a facile way to prepare epitaxial films at low temperature of 200 ºC with varied film thickness control (from 10 nm to 2 µm). The structure and morphologies of thin films are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses.