Bi 2 WO 6 /UiO-NH 2 -66 heterojunction photocatalysts with enhanced visible light organic pollutants removal

In this work, the flower-like hierarchical Bi 2 WO 6 decorated with nano UiO-NH 2 -66 was fabricated by a two-step solvothermal method. The structure, composition, and morphology of the composites were characterized by XRD, FTIR, XPS, BET, and SEM. The photoelectrochemical properties of the composites were analyzed by transient photocurrent response, DRS, and PL spectra. It is found that hole (·h + ) plays a dominant role, and the hydroxyl radical (·OH) and superoxide radical (·O 2 − ) play a secondary role in the catalytic system after free radical trapping experiments. The results of electron spin resonance spin-trapping tests also confirm the mechanism. Compared with pure Bi 2 WO 6 or pure UiO-NH 2 -66, Bi 2 WO 6 /UiO-NH 2 -66 composites have much higher decomposition effectiveness of Rhodamine B under the same conditions. Furthermore, Bi 2 WO 6 /UiO-NH 2 -66 photocatalyst with 7 wt% of UiO-NH 2 -66 (denoted as BWO/UNH-7) kept the stable catalytic performance after five recycles, which may be used as a good photocatalyst for degrading organic matter in sewage. Graphical abstract