CuWO4|MnWO4 heterojunction thin film with improved photoelectrochemical and photocatalytic properties using simulated solar irradiation

In this paper, we report the synthesis of CuWO4, MnWO4, and FTO vertical bar CuWO4 vertical bar MnWO4 as type II heterojunction thin film prepared by the drop-casting method. These thin films were synthesized by microwave-hydrothermal method with pure phase formation confirmed by X-ray diffraction (XRD), micro-Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses. The photoelectrochemical response of these films was investigated under simulated illumination with AM 1.5 G type filter. The heterojunction displayed photocurrent density values two times higher than the FTO vertical bar CuWO4 film, reaching 39 mu A/cm(2) at 1.23 V versus normal hydrogen electrode. Optical and electrochemical characterizations revealed superior visible light absorption and lower charge transfer resistance for the FTO vertical bar CuWO4 vertical bar MnWO4 heterojunction thin film. Low photoluminescence emission and transient photocurrent data confirmed a decreased electronic charge transfer between the valence and the conduction band, besides a reduced electron-hole recombination rate for the FTO vertical bar CuWO4 vertical bar MnWO4 heterojunction film. Mott-Schottky photocurrent response investigation revealed that the FTO vertical bar CuWO4 vertical bar MnWO4 heterojunction thin film can be considered an excellent photoanode for photoelectrocatalytic applications under solar irradiation. Finally, the heterojunction exhibited better performance for the photodegradation of Rhodamine B (RhB), corresponding to 55.5% at 165 min.

Automated summary

In this paper, CuWO4, MnWO4, and FTO vertical bar CuWO4 vertical bar MnWO4 type II heterojunction thin films were synthesized by the drop-casting method. The films exhibited high photocurrent density and visible light absorption, low charge transfer resistance, and reduced electron-hole recombination rate, making them suitable for photoelectrocatalytic applications.