Boosting visible light photocatalytic activity via impregnation-induced RhB-sensitized MIL-125(Ti)

The visible light driven pollutant degradation by photocatalysis is one of the most effective and environmentally friendly strategies, which urgently requires the highly efficient catalysis. In this study, the RhB-sensitized MIL-125(Ti) photocatalyst (RhB/MIL-125) was obtained by post-impregnation strategy in dark, owing to its remarkable adsorption and structure properties of MIL-125(Ti). The nanostructure, morphology and optical properties of as-prepared RhB/MIL-125 catalyst were characterized by various physicochemical methods in detail. It was found that the RhB was successfully incorporated into the MIL-125(Ti) matrix. Excitingly, the obtained RhB-sensitized MIL-125(Ti) showed a boosted photocatalytic performance with the removal rate of MO beyond 90% in 60 min under visible light (lambda > 420 nm) and exhibited the well stability during recycle tests. The hole (h(+) and superoxide free radical (center dot O-2(-)) were the key reactive species during the photodegradation process and the possible photocatalytic mechanism of RhB/MIL-125 for MO degradation was proposed. Our new photocatalyst can inspire the in-depth understanding in the visible light driven process and accelerate the nanoporous materials for real-life energy and environmental applications. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.