Synthesis of novel CdSe QDs/BiFeO3 composite catalysts and its application for the photo-Fenton catalytic degradation of phenol

Heterogeneous photo-Fenton reaction using BiFeO3 as catalyst was considered as an efficient environmental remediation technique. However, its low catalytic performance limited its application. In this work, CdSe QDs with high electron mobility, small size effect and rich surface properties were loaded on BFO surface by stirring impregnation method. The photo-Fenton catalytic performance of catalysts under visible light irradiation was evaluated by the degradation of phenol. The results showed that the BFO with CdSe QDs uniformly distributed on the surface shows much better photo-Fenton degradation of phenol performance than that of pure BFO. Moreover, when the load content of CdSe QDs comes to 0.5 wt%, the degradation efficiency of phenol increased from 41.5% to 98.5% within 60 min. The results of photochemical experiments confirmed that composite catalyst had a good ability to separate photo-induced carriers and the experiments of free radicals trapping showed that the holes and OH radicals were important active substances. Based on the above research, the possible mechanism of photo-Fenton reaction of catalyst was expounded. Excellent photo-Fenton catalytic performance and superior stability make this material showing a good application prospect for the degradation of organic pollutants in wastewater.