Plasmonic hot electrons: Potential candidates for improved photocatalytic hydrogen production

The photocatalytic water splitting is an emerging way of solar to hydrogen conversion due to its cheap and clean nature. The plasmon excitations in metallic sub-wavelength nanostructures are improving the semi-conductor industry through broadening of ab-sorption range, enhancing charge separation and surging optical density of states in coupled semi-conductor. Besides these traditional enhancement mechanisms, the semi-conductor can be externally charged by additional carriers generated from plasmon-decay in ultrafast time scales. The mechanisms behind the generation of these metallic hot electrons and their transfer to semiconductor for enhanced photocatalytic hydrogen production have been reviewed. Furthermore, the road barriers limiting the efficiency of photocatalytic water splitting and its possible solutions through coupling with plasmonic resonators are presented. The possible problems and the expected solutions are proposed with the help of reasonable literature providing perspective for future research. This research finds its importance not only in green energy but opto-electronic industry as well.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.