Indium-doped TiO2 nanorod arrays for high-efficiency photoelectrochemical water splitting

Through the hydrothermal synthesis of indium-doped titanium dioxide (In–TiO 2 ), we observed that the indium element intricately integrated into the rutile TiO 2 lattice, leading to surface protrusions on the nanorods, forming aggregated nanorod structures. This unique nanostructure not only significantly increases the specific surface area of the nanomaterial but also effectively enhances the efficiency of charge transfer and light absorption. Through validation by various structural characterization methods, including high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS), we confirmed the presence of this structure. This series of validations provides a solid theoretical foundation and experimental evidence for our research. The performance test results show that at 1.23 V, the In–TiO 2 exhibits an impressive photocurrent density of 4.78 mA cm 2 compared to the standard reference electrode, 3.5 times higher than that of pure TiO 2 under AM 1.5 G illumination conditions. Furthermore, the hydrogen production rate of In–TiO 2 is approximately 0.103 mmol h cm −2 , significantly higher than that of pure rutile TiO 2 , which is 0.046 mmol h cm −2 . This study profoundly reveals the importance of indium doping in the TiO 2 lattice for enhancing the efficiency of photocatalytic hydrogen production, providing valuable insights for the future development of photocatalytic technology. As research on novel photocatalysts advances, we look forward to further breakthroughs and progress, aiming to make greater contributions to addressing energy and environmental challenges.