Photocatalytic degradation of gaseous toluene with multiphase TixZr1- xO2 synthesized via co-precipitation route

Abstract

In the present work, the multiphase TixZr1−xO2 particles containing cubic-phase ZrO2 were fabricated via co-precipitation route. The mole ratios of Ti and Zr elements were controlled by three levels: Ti/Zr = 7/3 (maximum), Ti/Zr = 5/5 (medium), and Ti/Zr = 3/7 (minimum). The materials prepared were characterized by using X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. For the maximum usage of solar power with fabricated catalysts, elimination of gaseous toluene was chosen as a model to evaluate the performances under visible light. The results indicated that the degradation efficiency of toluene was about 80% after 6 h reaction using Ti0.3Zr0.7O2 as the photocatalyst. On the other hand, the multiphase TixZr1−xO2 (x = 0.7 or 0.5) photocatalysts showed significant enhancement in the activity, compared with the commercial TiO2 (Degussa P25). The enhanced performances of TixZr1−xO2 might be attributed to the lower charge recombination rate of photoinduced electron–hole pairs. In addition, some intermediates (the benzaldehyde and benzoic acid) and final product (CO2) adsorbed on the surface of the particles were also detected by using in situ Fourier transform infrared (FTIR) spectroscopy.