Investigation of the morphology, structural, optical, and photoelectrochemical properties of WO3–Fe2O3/CrTiO2 thin-film photoanodes for water splitting

Abstract

CrTiO2 nanotube, tungsten-modified CrTiO2, iron-modified CrTiO2 and tungsten–iron-modified CrTiO2 have been prepared by facile one-step anodization coupled with chemical bath deposition method. XRD, FE-SEM, EDX mapping and UV–Vis spectroscopy were used to characterize the synthetic samples. The impacts of these compounds on the photoelectrochemical activities of modified CrTiO2 photoelectrodes have been studied. Photoelectrochemical (PEC) water splitting performance of bare CrTiO2 nanotube photoelectrodes has remarkably been increased by hybrid tungsten–iron–CrTiO2 nanotube composite photoelectrodes. Good photoelectrocatalytic and stable photoelectrochemical performance have been shown by tungsten–iron–CrTiO2 (denoted as S6). The synergistic effect of WO3, Fe2O3 and CrTiO2 can be accounted for the considerable increase in the performance of tungsten–iron-modified CrTiO2, enhancement of optical absorption in the visible region and the suitable band positions of these composites. Ultimately, the recyclability of the synthetic tungsten–iron-modified CrTiO2 photocatalysts showed the good stability of their photocatalytic activity.