Immobilized WO3/W18O49 trunk-branch nanostructure: A homojunction improved adsorption and photocatalytic performance

Constructing homojunction hierarchical nanostructures with intimate contact and favorable carriers separation is an effective and challenging strategy to obtain efficient photocatalysts. We here report an immobilized WO3/W18O49 homojunction photocatalyst with W18O49 branches growing out of WO3 trunks. Under simulated sunlight irradiation, the optimal WO3/W18O49 composite exhibits enhanced adsorption and photocatalytic performance, which are 10.69 and 3.61 times higher than those of WO3, respectively. The superior performance is ascribed to the well-distributed trunk-branch structure, surface charge and effective charge transfer and separation in the homojunction composites, which was verified by experimental characterizations and the density functional theory (DFT) calculation. This work provides a solid foundation for further study and may give rise to the design of other photocatalysts.