Construction of a novel 0D-3D boron nitride quantum dots /NH2-MIL-125(Ti) composite for photodegradation of Rhodamine B

The development of efficient and stable composite photocatalytic materials is an urgent need in the current environmental field. In this paper, NH2-MIL-125(Ti) composite photocatalytic materials modified by boron nitride quantum dots (BNQDs) with different contents were successfully prepared by coprecipitation method. The microstructures of BNQDs/NH2-MIL-125(Ti)(NMTB-x) composites were characterized by XRD, FT-IR, SEM, EDS, TEM, XPS and BET techniques. The results of UV–vis, PL and EIS have confirmed that NMTB-0.7 has a narrower bandgap and an excellent photo-generated carrier separation rate. The photocatalytic activity of NMTB-x for degradation of dye wastewater Rhodamine B (RhB) was also evaluated. The results showed that NMTB-0.7 had excellent photocatalytic degradation performance for RhB, and its photocatalytic performance was far superior to pure NH2-MIL-125(Ti)(NMT). The excellent photocatalytic performance of NMTB-0.7 may be due to the introduction of BNQDs promotes the separation efficiency of photo-generated electron-hole pairs and accelerates the carrier transfer. The stability of NMTB-0.7 composite was tested by cyclic experiments, and its photocatalytic activity remained above 80% after five cycles. Finally, the photocatalytic mechanism of NMTB-x composite has proved by free radical capture experiments.