Novel heterostructured NaTaO₃/WO₃ systems with improved photocatalytic properties for water decontamination under UV and Visible illumination

In this work, we present the preparation of NaTaO₃/WO₃ systems, a broad-bandgap and a narrow-bandgap semiconductor, respectively, for photocatalytic applications. The samples were prepared by two different methods, microwave-assisted and conventional hydrothermal method, with different NaTaO₃/WO₃ molar ratios. All samples were extensively characterized, and the photocatalytic behavior was studied in the degradation reaction of rhodamine B under simulated solar illumination. A significant synergistic effect in the coupling of the two components could be observed, with an important improvement in the rhodamine degradation rate, especially for the microwave-prepared sample with 1:1 (NaTaO₃/WO₃) molar ratio. The enhancement of the activity can be explained by the formation of type II and Z-Scheme heterojunctions. The obtained results are promising for the development of more efficient photocatalyst materials under solar or visible illumination.