Engineering <scp> TiO ₂ </scp> photocatalysts for maximum hydrogen evolution: A review

Abstract Photocatalytic water splitting with titanium dioxide (TiO₂) is a key step toward producing hydrogen in a way that is good for the environment. This review carefully puts together and looks at the methodologies for making TiO₂‐based photocatalysts that have reasonably large hydrogen evolution rates that have been published in the last few years. We analyze the essential factors influencing photocatalytic efficiency, encompassing nano‐structural morphology (such as nanotubes, nanosheets, and quantum dots), metal and non‐metal doping (e.g., Cu, Ni, F), the creation of heterojunctions (e.g., with g‐C 3 N 4 , CdS, graphene), and the utilization of phenomena like the SPR effect and oxygen vacancies. An assessment of the performance of advanced systems, including Z‐scheme heterostructures and perovskite‐TiO 2 composites, is conducted. The paper also talks about how important operating parameters like sacrificial agents, pH, light intensity, and photocatalyst concentration are. This analysis not only summarizes the state of the art by comparing their notably high hydrogen yields and talking about new uses in wastewater treatment, but it also talks about the problems that need to be solved and the steps that need to be taken to make solar‐driven hydrogen production via TiO 2 photocatalysis commercially viable on a large scale.