Photocatalytic degradation of NO_x and ethanol in the gas phase by spray dried Ce-TiO₂

We synthesized Ce doped TiO2 (Ce-x-T) and tested it in the photocatalytic degradation of NOx and ethanol under visible light. Pristine TiO2 (T) and different dopant ratios of Ce-TiO2 (Ce-x-T; x = 0-1.0 wt%) were prepared by a water-based sol-gel method followed by spray drying. The successful doping of Ce in the lattice structure of TiO2 was confirmed by several characterizations such as X-ray diffraction (XRD), energy dispersive X-ray (EDX), Fourier transform infrared (FTIR), and Raman spectroscopy. All the prepared catalysts grew as spherical grains with a polycrystalline anatase phase. Ce0.8T revealed the lowest bandgap among all the prepared catalysts (2.8 eV) compared to 3.2 eV for T. The highest degradation of NOx and ethanol was attained by Ce0.8T (26 +/- 1% and 23 +/- 1%), which was 2.8 and 1.5 times the degradation by T, Furthermore, we proposed the photocatalytic degradation mechanism by the reactive oxidant species (ROS).