Comprehensive Evaluation of Nanosized Bismuth Tungstate (Bi2WO6) as Photoanodes for Photoelectrochemical Water Splitting Performance.

Bismuth based metal oxides are regarded as potential candidates for fabricating photoelectrodes due to their cost-effectiveness, high stability, and significant light absorbing capability. Hence, our present study focuses on rendering an extensive evaluation of nano-sized bismuth tungstate (Bi2WO6) as photoanodes for photoelectrochemical water splitting activity. Bismuth tungstate nanoparticles have been prepared by a facile solvothermal route, and their structural, morphological, elemental composition, and optical properties have been characterized by employing powder X-ray diffraction analysis (PXRD), high-resolution scanning electron microscope (HRSEM), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (UV-DRS) technique. For Bi2WO6 sample, the onset potential obtained for OER under dark and light conditions are ηdark = 0.83 V and ηlight = 0.71 V vs. Ag/AgCl respectively. The magnitude of photocurrent density at 1.23 V vs. RHE has been measured as 0.17 µA/cm2. From the Mott–Schottky plot, the flat band potential (Efb) for Bi2WO6 photocatalyst has been obtained as − 0.38 V vs. Ag/AgCl. Nanosized Bi2WO6 exhibited low onset potential, good photocatalytic stability, and suitable band edge potentials facilitating them to act as an efficient photoanode under stimulated solar light irradiation. [ABSTRACT FROM AUTHOR]