Au@TiO2 yolk–shell hollow spheres for plasmon-induced photocatalytic reduction of CO2 to solar fuel via a local electromagnetic field

Abstract

An electric field in a photocatalytic system consisting of Au@TiO₂ yolk–shell hollow spheres is created to enhance the generation of electron–hole pairs and remit the charge-carrier recombination. Local surface plasmon resonance (LSPR)-mediated local electromagnetic field nearby Au nanoparticles cannot only enhance the local generation and subsequent separation of electron–hole pairs in TiO₂ shells to improve the photoreduction yield of CO₂, but also facilitate chemical reactions involving multiple e⁻/H⁺ transfer processes to allow the formation of high-grade carbon species (C₂H₆), which was rarely observed in precedent CO₂ photocatalytic reduction systems. The work may provide a new viewpoint for designing photocatalysts for artificial photosynthesis involving multiple reactions.