A review on plasmonic nanoparticle-semiconductor photocatalysts for water splitting

Transforming solar energy into chemicals through the photoelectrochemical or photocatalytic water-splitting process is considered a powerful technique for implementing an effective, clean, and affordable energy source. The main issues are charge carriers recombination, the large bandgap of the photocatalysts, and the occurrence of the back (water-forming) reaction. The decoration of plasmonic metal nanoparticles onto semiconductors has recently been reported as an auspicious technique to overcome these limitations and promote photocatalytic activity through the transfer of plasmonic energy from the plasmonic metal nanoparticles to the semiconductor. This review focuses on three main objectives: surveying the main features of the plasmonic metal nanostructure that influence its photocatalytic activity; providing a brief explanation of the four main mechanisms of the plasmonic energy transfer, and summarizing some noteworthy recent plasmonic photocatalysts which widely investigated for photocatalytic or photoelectrochemical water splitting with emphasis on their influence on the behavior of charge carriers. [Display omitted] •The semiconductor/PNPs composites can promote the PC activity of water-splitting.•Photocatalysts with high crystallinity exhibit high activity for water splitting.•Plasmonic energy transfer to the semiconductor via light trapping, HEI, and PIRET.•Water-splitting systems should be designed to work across the whole solar spectrum.