Preparation and characterization of WTiO2 nanotubes decorated with Prussian blue nanoparticles and nanocubes with enhanced photoelectrochemical properties

Successive ionic layer adsorption and reaction (SILAR) method has been used to decorate Prussian blue (PB) on tungsten-doped titanium oxide nanotubes (WTiO 2 ). Scanning electron microscopy (SEM), X-ray diffraction (XRD), EDX, and UV-Vis-DRS methods have been used to characterize the morphology, phase composition, elemental composition, and optical properties of the samples prepared. The PB/WTiO 2 samples prepared were then used as photoanodes in photoelectrochemical water splitting to yield hydrogen. The morphology, optical property, and photoelectrochemical performance of the prepared samples were highly affected by the SILAR deposition cycle, according to the results obtained. The sample with PB deposited in 9 SILAR cycles (sample S9) showed the highest photocurrent value (0.118 mA/cm 2 ) under illumination. This enhancement is mostly due to visible light harvesting and reduced recombination of photo-generated electron-hole pairs, resulting from the synergistic effect of the heterojunction and the well-organized morphology of WTiO 2 .