Ab initio study of plasmon-induced direct hot-electron transfer at metal-acceptor interfaces

Plasmon-induced hot-electron transfer at metal-molecule and metal-semiconductor interfaces is an important step in photocatalysis, photodetection and photovoltaics. The hot-electron transfer can occur via two mechanisms: (i) indirect transfer, where the hot electrons and holes are first produced in the metal nanostructure and eventually get transferred to the acceptor, (ii) direct transfer, where the plasmons decay by directly exciting an electron from the metal to the acceptor. Controlling and favoring the direct transfer process is crucial as one can bypass the electron-electron scattering step in the metal, thus avoiding energy losses. However, the atomic-level details and knowledge of the efficiency of this direct transfer process are missing. Using model metal-acceptor interfaces, we present an ab initio study based on time-dependent density functional theory (TDDFT) calculations to address this issue. We envision our computations to provide theoretical guidelines to design more efficient metal-molecule and metal-semiconductor interfaces.