Plasmonic photocatalysts for enhanced solar hydrogen production: A comprehensive review

Abstract

TiO2 is a photocatalyst material with a bandgap of approximately 3.2 eV (380 nm). It produces green hydrogen via water splitting of H2O → H2 + 1/2 O2 with an activation energy Ea = 2.46 eV (237 kJ/mol) in artificial photosynthesis. Considering that the ultraviolet (UV) light constitutes approximately only 5% of incident solar irradiation, there have been extensive efforts to develop a method of the extension to the longer wavelength regions. Plasmon-enhanced photocatalytic hydrogen production has the advantage of utilizing the visible (VIS) and near-infrared (NIR) regions in the solar spectrum. Collective electronic oscillation on noble metal surfaces can supply hot electrons and holes to facilitate hydrogen production. Hot electrons can undergo dynamic processes of photoemission, photodesorption, and photoconversions on the surfaces. Noble metals can be hybridized onto semiconductors and other two-dimensional materials to enhance green hydrogen. Localized surface plasmon resonance (LSPR) can contribute to the accelerated electron transfer including plasmon-induced resonance energy transfer (PIRET). In this work the dynamics of hot carriers in plasmon is reviewed in a comprehensive way toward more efficient green hydrogen production. © 2023 Elsevier Ltd