TiO2 thin films with various Mo concentrations have been deposited on glass and n-type silicon (100) substrates by this radio-frequency (RF) reactive magnetron sputtering at 400°C substrate temperature. The crystal structure, surface morphology, composition, and elemental oxidation states of the films have been analyzed by using X-ray diffraction, field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy, respectively. Ultraviolet-visible spectroscopy has been used to investigate the degradation, transmittance, and absorption properties of doped and undoped TiO2 films. The photocatalytic degradation activity of the films was evaluated by using methylene blue under a light intensity of 100 mW cm−2. The X-ray diffraction patterns show the presence of anatase phase of TiO2 in the developed films. X-ray photoelectron spectroscopy studies have confirmed that Mo is present only as Mo6+ ions in all films. The Mo/TiO2 band gap decreases from ~3.3 to 3.1 eV with increasing Mo dopant concentrations. Dye degradation of ~60% is observed in Mo/TiO2 samples, which is much higher than that of pure TiO2.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIP) (no. 2015R1C1A2A01052256).
Copyright © 2017 John Wiley & Sons, Ltd.
- band gap
- dye degradation
- thin film
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry