Temperature matters: An infrared spectroscopic investigation on the photocatalytic efficiency of titania coatings

Titania is one of the most studied photocatalytic materials for self-cleaning applications. To maximize the photocatalytic efficiency, different strategies are currently under investigation, such as control of the nano- or microstructure, optimization of the crystalline phase and addition of doping agents. A parameter too often neglected is temperature, which dramatically affects the self-cleaning processes in thin titanium dioxide (TiO₂) films. In this study, we prepared a titania coating using the sol-gel route. Stearic acid and a triblock copolymer (Pluronic F127) were used as model pollutants. A dedicated heating cell was used to precisely control the temperature. The infrared spectroscopy was used to follow the amount of residual pollutant agents within 60 minutes every 10 °C. The photocatalytic reaction rate was calculated for the stearic acid in the 25-60 °C range.