Plasmon-generated hot holes for chemical reactions

Plasmonic nanostructures have been widely used for photochemical conversions due to their unique and easy-tuning optical properties in visible and near-infrared range. Compared with the plasmon-generated hot electrons, the hot holes usually have a shorter lifetime, which makes them more difficult to drive redox reactions. This review focuses on the photochemistry driven by the plasmon-generated hot holes. First, we discuss the generation and energy distribution of the plasmon-generated hot carriers, especially hot holes. Then, the dynamics of the hot holes are discussed at the interface between plasmonic metal and semiconductor or adsorbed molecules. Afterwards, the utilization of these hot holes in redox reactions is reviewed on the plasmon-semiconductor heterostructures as well as on the surface of the molecule-adsorbed plasmonic metals. Finally, the remaining challenges and future perspectives in this field are presented. This review will be helpful for further improving the efficiency of the photochemical reactions involving the plasmon-generated hot holes and expanding the applications of these hot holes in varieties of chemical reactions, especially the ones with high conversion rate and selectivity.