Heterojunction photocatalyst for organic degradation: Superior photocatalytic activity through the phase and interface engineering

Semiconductor-based heterostructure photocatalyst attracts extensive attention because of its excellent interface charge transfer/separation ability. Here, the beta-Bi2O3/CeO2 heterostructure photocatalysts are fabricated via a simple mechanochemical couple with thermal decomposition strategy. The introduction of CeO2 can not only stabilize the phase of beta-Bi2O3/CeO2 but also construct a heterojunction at the interface, resulting in the improved visible light response capability and efficient transfer and separation of photo-generated charges. Besides, the increased specific surface area and pore volume increase the active sites to accelerate the adsorption and mass transfer process. As a result, the beta-Bi2O3/CeO2 heterostructure photocatalyst shows remarkably enhanced photocatalytic performance towards malachite green (MG) degradation under visible-light irradiation compared with the Bi2O3 and CeO2. The degradation efficiency of MG over the optimized beta-Bi2O3/CeO2 heterostructure reaches up to 97.5% after 2 h of visible-light irradiation. This work provides a new approach for the rational design of heterojunction photocatalyst combined with phase and interface engineering and opens up a potential avenue for efficient application of Bi2O3 photocatalyst for efficient energy conversion.