Photocatalytic activity of Zn2SnO4 coating deposited by air plasma spraying
Amir Hossein Navidpour, Mohammad Fakhrzad
Abstract
In the present research study, zinc stannate was synthesized using high energy mechanical milling of zinc oxide and tin oxide powders with a molar ratio of 2:1, respectively. The synthesized Zn2SnO4 feedstock powder was deposited on a 316 stainless steel plate by atmospheric plasma spraying. X-ray diffraction, Fourier Transform Infrared (FT-IR) analysis, Scanning electron microscope (SEM) and UV–Vis diffuse reflectance spectroscopy (DRS) were used for the phase analysis, analysis of patterns of vibration, evaluation of micrographs and photo-absorption ability, respectively; and methylene blue solution with a concentration of 6 mg/L was used to study the photocatalytic activity of the plasma-sprayed Zn2SnO4, and it was compared with those of the plasma-sprayed ZnO and the plasma-sprayed SnO2 as its binary counterparts. The band gap energy of plasma sprayed Zn2SnO4 and Zn2SnO4 feedstock powder were 3.1 and 3.6 eV, respectively. Zn2SnO4 coating also showed higher photocatalytic activity than that of SnO2 coating. It was concluded that although plasma spraying could be used as a promising method to deposit Zn2SnO4, further attempts are needed to enhance its light-harvesting and photocatalytic efficiency.