Experimental study on photocatalytic degradation efficiency of mixed crystal nano-TiO<sub>2</sub> concrete
Zhan Guo, Chenxiang Huang, Yu Chen
Abstract
Abstract The photocatalytic mixed crystal nano-TiO 2 particles were incorporated with concrete by means of the internal doping method (IDM) and spraying method (SPM) in this paper. To evaluate the photocatalytic degradation efficiency of mixed crystal nano-TiO 2 concrete, the methyl orange (MO) was chosen to simulate pollutants. The physicochemical characteristics and photocatalytic performance of mixed crystal nano-TiO 2 concrete prepared by above two different methods were experimentally investigated under UV irradiation and solar irradiation. Furthermore, the effects of two key influential factors including pollutant concentration and irradiation condition were also analyzed and discussed. Experimental results indicate that the nano-TiO 2 concrete prepared by the spraying method (SPM) exhibits maximum photocatalytic degradation efficiency of 73.82% when the sprayed nano-TiO 2 slurry concentration is 10mg/L. The photocatalytic degradation efficiency of unpolished nano-TiO 2 concrete is much higher than that of polished nano-TiO 2 concrete under the same exposure time of UV irradiation. Moreover, the photocatalytic degradation efficiency of nano-TiO 2 concrete decreases with the increase of pollutant concentration. The irradiation condition has an obvious influence on the photocatalytic degradation efficiency of nano-TiO 2 concrete. In the aspect of applications, the practical recommendations for the nano-TiO 2 concrete with self-cleaning capacity were presented according to the experimental results.