Characterization and photocatalytic activity of titanium dioxide deposited on stainless steel by pulsed-pressure MOCVD

Abstract

Titanium dioxide (TiO2) was deposited on stainless steel 304 by pulsed-pressure metalorganic chemical vapor deposition (PP-MOCVD). Titanium tetraisopropoxide (TTIP) in toluene at the concentration of 0.5 mol% was used as the precursor. The deposition was conducted at the base pressure of 300 Pa and deposition temperatures were varied between 350°C and 400°C. At these deposition temperatures, anatase phase is expected for further photocatalysis study. The deposited TiO2 thin films at the thickness of hundreds nanometers were analyzed using field emission scanning electron microscopy (FESEM) for surface morphology. X-ray diffraction (XRD) was applied for phase analysis. The contact angle was measured to study its relationship with surface morphology, grain size and phase. Finally, photocatalytic activity was investigated through the absorption of methylene blue using UV/Vis spectrophotometer. The deposited TiO2 thin films were found to be rutile and anatase with various surface morphology and grain size depends on the deposition temperature. The hydrophobicity of depositedTiO2 thin films tend to increase with the deposition temperature whereas the photocatalytic property depends on the microstructure of TiO2 thin film.