Isotope Effects in Plasmonic Photosynthesis
Sungju Yu, Prashant K. Jain
Abstract
Abstract The photoexcitation of plasmonic nanoparticles has been shown to drive multistep, multicarrier transformations, such as the conversion of CO 2 into hydrocarbons. But for such plasmon‐driven chemistry to be precisely understood and modeled, the critical photoinitiation step in the reaction cascade must be identified. We meet this goal by measuring H/D and 12 C/ 13 C kinetic isotope effects (KIEs) in plasmonic photosynthesis. In particular, we found that the substitution of H 2 O with D 2 O slows hydrocarbon production by a factor of 5–8. This primary H/D KIE leads to the inference that hole‐driven scission of the O−H bond in H 2 O is a critical, limiting step in plasmonic photosynthesis. This study advances mechanistic understanding of light‐driven chemical reactions on plasmonic nanoparticles.