Non‐thermal Effect of Atmospheric‐Pressure RF Cold Plasma on Photocatalytic Activity of As‐deposited TiO₂ Film

Abstract

Abstract TiO 2 film is deposited by atmospheric‐pressure (AP), radio‐frequency (RF), dielectric barrier discharge (DBD) plasma at a low power using titanium tetraisopropoxide (TTIP) and O 2 as the precursors. The morphology, optical properties, and crystalline structure of the as‐deposited TiO 2 film are investigated by using scanning electron microscopy (SEM), atomic force microscopy (AFM), ultraviolet‐visible (UV‐vis) absorption spectroscopy, and Raman spectroscopy. The as‐deposited TiO 2 film show high photocatalytic activity in complete oxidation of HCHO to CO 2 and degradation of stearic acid. The gas temperature in the RF‐DBD plasma is estimated to be at about 500 K by the rotational temperature via optical emission spectroscopy (OES). The experimental results of amorphous TiO 2 film treated by the RF‐DBD plasma further exclude the likelihood of thermal effects derived from the plasma on crystallization of TiO 2 film. It is confirmed that the non‐thermal effect of the RF‐DBD plasma on the high photocatalytic activity of the as‐deposited TiO 2 film does exist.