Ultrafast proton-coupled electron transfer in heterogeneous photocatalysis

Jin Zhao, Ken Onda, Bin Li, Hrvoje Petek

研究成果: Chapter in Book/Report/Conference proceedingConference contribution

1 被引用数 (Scopus)

抄録

At metal-oxide/protic-solvent interfaces, partially hydrated or "wet electron" states represent the lowest energy pathway for electron transfer. Here we study the photoinduced charge transfer at the H 2O/TiO 2(110) interface by means of time-resolved two-photon photoemission spectroscopy and electronic structure theory. At ∼1 monolayer coverage of H 2O on partially hydroxylated TiO 2 surfaces we find an unoccupied electronic state 2.4±0.1 eV above the Fermi level. Density functional theory shows this to be a two-dimensional "wet electron" state, which is distinct from hydrated electrons observed on water-covered metal surfaces. The decay of electrons from the wet electron state by the resonant charge transfer to the conduction band of TiO 2 occurs in ≤15 femtoseconds. Similar unoccupied electronic structure is observed for CH 3OH covered TiO 2(110) surfaces; however, the electron dynamics are considerably more complex. The wet electron state dynamics of CH 3OH/TiO 2 exhibit both energy and population decay. The excited state lifetime is strongly coverage dependent increasing to >100 fs range above 1 ML CH 3OH coverage. Significantly, a pronounced deuterium isotope effect (CH 3OD) indicates a strong correlation between the interfacial electron transfer and the motion of protons in the molecular overlayer.

本文言語英語
ホスト出版物のタイトルPhysical Chemistry of Interfaces and Nanomaterials V
DOI
出版ステータス出版済み - 2006
外部発表はい
イベントPhysical Chemistry of Interfaces and Nanomaterials V - San Diego, CA, 米国
継続期間: 8 15 20068 17 2006

出版物シリーズ

名前Proceedings of SPIE - The International Society for Optical Engineering
6325
ISSN(印刷版)0277-786X

その他

その他Physical Chemistry of Interfaces and Nanomaterials V
国/地域米国
CitySan Diego, CA
Period8/15/068/17/06

All Science Journal Classification (ASJC) codes

  • 電子材料、光学材料、および磁性材料
  • 凝縮系物理学
  • コンピュータ サイエンスの応用
  • 応用数学
  • 電子工学および電気工学

フィンガープリント

「Ultrafast proton-coupled electron transfer in heterogeneous photocatalysis」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル