Bi Quantum Dots Supported on BiOBr Nanoparticles and Loaded on Porous ZnO as a Photocatalyst for Dye Degradation and H2 Production.

Synergetic photocatalytic H₂ production by organic dye photodegradation is always a goal. However, the related research has been hindered due to the uncontrollability of this process. This study prepares the ZnO/Bi-QDs/BiOBr photocatalyst, and the hole (h⁺) aggregation phase (ZnO) is constructed into a lamellar porous structure to improve its adsorption capacity for dyes based on the energy level structure of the composite. By this method, the reactive groups used for photodegradation of dyes are controlled to h⁺ and ^•OH, e^– is used for photocatalytic H₂ production, and the synergistic effect of dye photodegradation and photocatalytic H₂ production is realized. Under the action of this photocatalyst and visible light, rhodamine B (RhB) is completely degraded in 8 min, the time can be reduced to 2 min when pH is 5, and it can realize the complete degradation of RhB in 120 min under natural sunlight. The H₂ production rate reaches 1678 μmol·g^–1·h^–1 in RhB (h⁺ scavenger) aqueous solution under visible light. This study provides an effective method and design idea for the design of photocatalysts with photocatalytic H₂ production during the photodegradation of organic dyes. [ABSTRACT FROM AUTHOR]