Facile fabrication of perovskite-incorporated hierarchically mesoporous/macroporous silica for efficient photoassisted-Fenton degradation of dye

摘要

LaFeO3-doped hierarchically mesoporous/macroporous silica (LFO/MMS) was prepared for the first time by impregnation method and then calcination. The sample was characterized in detail, suggesting the successful incorporation of LFO into MMS which was consisting of mesopores and macropores. The high surface area, accessible pores as well as low band gap energy supported its high performance towards efficient photoassisted-Fenton degradation of dye under visible light irradiation. Rhodamine B (RhB), which has been widely used as one of typical synthetic dyes in textile industry, was selected as the dye model. It was found that the incorporation of LFO into the MMS support induced a significant enhancement in the visible-light photo-Fenton catalytic performance, as compared with pure LFO. The degradation rate using LFO/MMS under the conditions (temperature = 25 degrees C, catalyst dosage = 1 g L-1, initial dye concentration = 10 mg L-1, initial H2O2 concentration = 10 mM and initial pH = 6) was 95.6% after 90-min exposure to the visible light. This was 7% and 19.8% greater than that of LFO and MMS, respectively. In particular, the pseudo-first-order reaction rate constant for LFO/MMS was 0.0367 min(-1), which was approximately 2 times higher than that for pure LFO (0.0215 min(-1)). The newly developed catalyst, LFO/MMS, showed a good stability for recycle and reuse, which is crucial for its potential use in industrial application.