A review of recent modification strategies of TiO2-based photoanodes for efficient photoelectrochemical water splitting performance

To address concerns about greenhouse gas emissions and sea level rise brought on by global climate change, hydrogen (H2) has the capacity to substitute fossil fuels as a carbon-free source of energy. The most reliable method of producing H2 is photoelectrochemical (PEC) water splitting, which uses water and solar as renewable energy sources. Titanium dioxide (TiO2) is one of the excellent semiconductors utilized as an effective photoanode in PEC water splitting due to its efficient light absorption, cost-effectiveness and excellent photostability. The primary emphasis of this review was on the various techniques used to modify TiO2-based photoanodes and presents a comprehensive overview of the latest progress made towards improving their effectiveness for PEC water splitting. It involves different preparation methods of TiO2-based photoanodes such as hydrothermal, chemical vapor, physical vapor, electrochemical deposition, and other methods which plays a crucial role in determining their structural, morphological, and surface properties. These properties, in turn, influence the light absorption, charge transport, and PEC water splitting activity, ultimately affecting the effectiveness and efficiency of PEC water splitting. Furthermore, elaboration on the outcomes of modification on the physical-chemical-optical features of TiO2-based photoanodes that result from preparation methods is included in this review. The review provides valuable understanding regarding the creation and advancement of high-performing TiO2-based photoanodes in the sustainable energy generation.