Collecting hot electrons excited by photon absorption has obtained much attention because it is promising way to create efficient photovoltaics, photodetection, and photocatalysts. However, photoexcited hot electrons undergo thermalization so rapidly that they are difficult to extract, which is a major obstacle for practical applications. In this respect, hybrid lead iodide perovskite (MAPbI3) is a strong candidate as a light absorbing material in hot electron photovoltaics, because it has a long hot carrier lifetime and the diffusion length compares to other semiconductors. With this motivation, we demonstrated a MAPbI3 modified plasmonic Au-TiO2 nanodiode to enhance hot electron flow for effective extraction. By measuring the photocurrent and incident photon-to-current conversion efficiency, we observed an increased photo-to-electrical conversion efficiency. The time-resolved pump-probe experiment revealed an elongated hot electron lifetime in the perovskite modified plasmonic Au. We conclude that the synergetic results of perovskite and plasmonic Au are associated with effective hot electron capture by providing additional pathways and near-field enhancement. These findings could provide a novel approach for designing efficient hot carrier applications by increasing the hot electron induced photocurrent.

Amplified hot electron flow on perovskite modified plasmonic Au-TiO2 nanodiode

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.