A review on passivation engineering for improving photocatalytic hydrogen evolution performance

Photocatalytic hydrogen evolution (PHE) is a promising route for the energy-renewable and eco-friendly development of the future society, but the low activity and durability of photocatalysts seriously restrict the development of this technology. In this case, passivation engineering may provide a feasible idea to solve these problems, by which a relatively stable and mild environment can be formed to guarantee the high separation and utilization of photogenerated charge carriers. Recently, passivation engineering has been increasingly adopted for improving the activity and durability of photocatalysts, and thus, a comprehensive review will help researchers understand and use this technology to construct high-performance photocatalytic systems. Herein, firstly, the basic concept and the roles of the passivation technique in PHE are discussed. Subsequently, we introduce the commonly utilized synthesis methods, followed by the characterization techniques employed in passivation engineering. Thereafter, we review the categories and mechanism of passivation engineering in PHE. Lastly, the challenges and perspectives of passivation engineering for future practical applications are discussed. We hope that this review can provide some useful guidance and trigger interest in passivation engineering for the construction of high-performance photocatalysts.