TIME-DEPENDENT DENSITY FUNCTIONAL THEORY STUDIES OF CHARGE TRANSFER IN OXYGEN DISSOCIATION ON SILVER NANOPARTICLE

Abstract

We performed calculations to study the dominating charge transfer mechanism in an plasmon-mediated catalytic reaction, oxygen dissociation on Ag nanoparticles (NPs) by using time-dependent density functional theory. Two mechanisms, plasmon-induced hot-electron transfer (PHET) and direct interfacial charge transfer (DICT), were discussed. In order to study the effects of the size and shape of nanoparticles on the charge transfer, ten different geometries of Ag-NP-O$_2$ were considered. Real-time time-dependent density functional theory (RT-TDDFT) was used to obtain the evolution of electron density and energy. And fragment based Hirshfeld (FBH) population and Becke population were calculated to analyze the evolution of electron density and energy on the oxygen molecule. Linear-response time-dependent density functional theory (LR-TDDFT) calculations and natural transition orbitals (NTOs) analysis were performed to provide insights into the charge transfer process. The results of RT-TDDFT and LR-TDDFT are consistent with each other. It can be concluded that the PHET mechanism is the one dominating the charge transfer process while the DICT mechanism only has limited contribution.