In Situ Synthesis of Co-WO3 Anodic Layers for Enhanced Photoelectrochemical Water Splitting

Abstract

Photoelectrochemical water splitting under solar radiation is one of the most studied areas of science. However, there are still many problems connected with this topic such as the low efficiency of systems or their usability only in the region of ultraviolet radiation. Anodic metal oxides are used as working electrodes in PEC cells due to their unique geometry, relatively high surface area, simple preparation, and their unique properties. Nanostructured tungsten oxide is characterized by strong photocorrosion stability in aqueous solutions and stable physicochemical properties. The main advantage of this material is its bang gap energy (2.6 eV), which is much lower than that of the commonly used titanium dioxide (3.2 eV). In consequence, absorption in the visible light region is significantly increased (up to 12% of the solar spectrum). The main objective of this project is to develop and optimize the single-step fabrication method of cobalt-doped nanostructured anodic tungsten oxide with enhanced photoelectrochemical properties under solar radiation. Particular attention will be paid to finding the correlation between the concentration of Co2+ ions in the electrolyte and their amount embedded in the anodic layer. A complex characterization (SEM/EDS, XRD, XPS, UV-Vis DRS) of nanostructured Co-WO3 layers will be performed to establish correlations between material morphology, composition, structure, and its optical, semiconducting, spectro-, photo- and electrochemical properties.AcknowledgementsThis research was partially funded within the budget of the "Excellence Initiative - Research University" program at the Jagiellonian University in Krakow.