Overall water splitting and hydrogen peroxide synthesis by gold nanoparticle-based plasmonic photocatalysts

Plasmonic photocatalysts driven by the localized surface plasmon resonance excitation of gold nanoparticles (Au NPs) can be efficient solar-to-chemical converters due to their wide spectral response. This review article highlights recent studies on plasmonic water splitting and H₂O₂ synthesis from water and oxygen (O₂) with a particular emphasis placed on the electrocatalysis of Au NPs. The Introduction (Section 1) points to the importance of the establishment of solar hydrogen and oxygen cycles involving hydrogen (H₂) and hydrogen peroxide (H₂O₂) as the key compound, respectively, for realizing a "sustainable society". Section 2 deals with the basic action mechanisms of Au NP-based plasmonic photocatalysts. Section 3 treats the electrocatalytic activity of Au NPs for the half-reactions involved in the reactions. Section 4 describes recent advances in the plasmonic overall water splitting (4.1) and H₂O₂ synthesis (4.2). Finally, a summary is presented with the possible development direction in Section 5.