Highly Efficient Plasmon Induced Hot-Electron Transfer at Ag/TiO<sub>2</sub> Interface
Jia Song, Jinlin Long, Yawei Liu, Zihao Xu, Aimin Ge, Brandon D. Piercy, David A. Cullen, Ilia N. Ivanov, James R. McBride, Mark D. Losego, Tianquan Lian
Abstract
Plasmon induced hot carrier transfer is a promising novel approach for solar energy conversion, but its practical application is often hindered by its low efficiency. This work demonstrates an unprecedented quantum efficiency of plasmonic hot-electron transfer of up to 53 ± 2% from 1.7 nm silver nanoparticles to anatase nanoporous TiO2 films at 400 nm excitation. This efficient hot-electron transfer consists of contributions of both hot electrons generated by plasmon decay through exciting Ag intraband transitions and Ag-to-TiO2 interfacial charge-transfer transitions. The efficiencies of both pathways increase at smaller Ag particle sizes from 5.9 to 1.7 nm, suggesting that decreasing particle sizes is a promising way toward efficient plasmonic hot-carrier extraction.