Facile synthesis of NH2-MIL-53(Al)@BiOBr@CQDs ternary heterostructure photocatalyst for degradation of ciprofloxacin in water

The construction of ternary heterojunction photocatalysts can achieve multi-gradient transfer of charges and accurate control the position of photogenerated electrons which has received increasing attention. In this paper, NH 2 -MIL-53(Al)@BiOBr@CQDs-10 % (ABCQDs-10 %) was prepared via a facile hydrothermal and chemical synthesis processes. Three-dimensional serration of NH 2 -MIL-53(Al) as a platform for irregular BiOBr nanosheets, CQDs promote interfacial contact and act as electron transport channels between BiOBr and NH 2 -MIL-53(Al) and constitute Z-type heterojunctions with high redox properties. ABCQDs-10 % shows the best photocatalytic removal efficiency (94.24 %) of CIP, the reaction rate constants (0.045 min −1 ) were 1.2 and 64 times higher than BiOBr and NH 2 -MIL-53(Al), respectively. The excellent degradation performance is attributed to the construction of Z-type heterojunction of NH 2 -MIL-53(Al)@BiOBr@CQDs which improve electron-hole separation and transfer efficiency. The main active species was •O 2 - . The photocatalytic activity of ABCQDs-10 % had not obvious loss after cycle experiments and the crystal structure had no significant changes, means high stable photocatalytic activity.