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

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.