標題: Mechanism of Back Electron Transfer in an Intermolecular Photoinduced Electron Transfer Reaction: Solvent as a Charge Mediator
作者: Narra, Sudhakar
Nishimura, Yoshifumi
Witek, Henryk A.
Shigeto, Shinsuke
應用化學系
應用化學系分子科學碩博班
Department of Applied Chemistry
Institute of Molecular science
公開日期: 6-十月-2014
摘要: Back electron transfer (BET) is one of the important processes that govern the decay of generated ion pairs in intermolecular photoinduced electron transfer reactions. Unfortunately, a detailed mechanism of BET reactions remains largely unknown in spite of their importance for the development of molecular photovoltaic structures. Here, we examine the BET reaction of pyrene (Py) and 1,4-dicyanobenzene (DCB) in acetonitrile (ACN) by using time-resolved near-and mid-IR spectroscopy. The Py dimer radical cation (Py-2(center dot+)) and DCB radical anion (DCB center dot-) generated after photoexcitation of Py show asynchronous decay kinetics. To account for this observation, we propose a reaction mechanism that involves electron transfer from DCB center dot- to the solvent and charge recombination between the resulting ACN dimer anion and Py-2(center dot+). The unique role of ACN as a charge mediator revealed herein could have implications for strategies that retard charge recombination in dye-sensitized solar cells.
URI: http://dx.doi.org/10.1002/cphc.201402411
http://hdl.handle.net/11536/25338
ISSN: 1439-4235
DOI: 10.1002/cphc.201402411
期刊: CHEMPHYSCHEM
Volume: 15
Issue: 14
起始頁: 2945
結束頁: 2950
顯示於類別:期刊論文