Tunable nonthermal distribution of hot electrons in a semiconductor injected from a plasmonic gold nanostructure
學年 106
學期 2
出版（發表）日期 2018-06-26
作品名稱 Tunable nonthermal distribution of hot electrons in a semiconductor injected from a plasmonic gold nanostructure
作品名稱（其他語言）
著者 S. K. Cushing; C. J. Chen; C. L. Dong; X. T. Kong; A. O. Govorov; R. S. Liu; N. Wu
單位
出版者
著錄名稱、卷期、頁數 ACS Nano 12(7), p.7117-7126
摘要 For semiconductors photosensitized with organic dyes or quantum dots, transferred electrons are usually considered thermalized at the conduction band edge. This study suggests that the electrons injected from a plasmonic metal into a thin semiconductor shell can be nonthermal with energy up to the plasmon frequency. In other words, the electrons injected into the semiconductor are still hot carriers. Photomodulated X-ray absorption measurements of the Ti L2,3 edge are compared before and after excitation of the plasmon in Au@TiO2 core–shell nanoparticles. Comparison with theoretical predictions of the X-ray absorption, which include the heating and state-filling effects from injected hot carriers, suggests that the electrons transferred from the plasmon remain nonthermal in the ∼10 nm TiO2 shell, due in part to a slow trapping in defect states. By repeating the measurements for spherical, rod-like, and star-like metal nanoparticles, the magnitude of the nonthermal distribution, peak energy, and number of injected hot electrons are confirmed to be tuned by the plasmon frequency and the sharp corners of the plasmonic nanostructure. The results suggest that plasmonic photosensitizers can not only extend the sunlight absorption spectral range of semiconductor-based devices but could also result in increased open circuit voltages and elevated thermodynamic driving forces for solar fuel generation in photoelectrochemical cells.
關鍵字 hot carriers; photocatalysis;photovoltaics;plasmonics;X-ray absorption
語言 en_US
ISSN 1936-0851
期刊性質 國外
收錄於 SCI
產學合作
通訊作者
審稿制度 否
國別 USA
公開徵稿
出版型式 ,電子版,紙本
相關連結

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/115544 )