Systematic investigation of heterogeneous interfacial charge transfer using single-molecule spectroscopy

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05398
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical chemistry
• Research Institution: Rikkyo University
• Principal Investigator: Mitsui Masaaki 立教大学, 理学部, 教授 (90333038)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 単一分子分光 / ヘテロ界面 / 電荷移動

Outline of Final Research Achievements

Charge transfer dynamics under interfaces and film environments were investigated using single-molecule spectroscopy as follows:
1) Photoblinking of single perylenediimide dyes in a poly(methylmethacrylate) (PMMA) film was investigated. We examined the bin-time dependencies of the cumulative distribution functions (CDF) of the on-time and off-time durations. The dispersive kinetics of on-time were attributed to radical ion pair ISC in PMMA. A simulation study revealed that the off-time CDF included power-law kinetics of charge hopping in the polymer. 2) Using a scanning MLE-KS method for a photoblinking analysis revealed multiple competitive kinetic processes at the interfaces between an Atto647N dye and TiO2. The injected electron from an excited dye to a trap state in TiO2 migrates due to trap-to-trap hopping, which follows power law kinetics, while the subsequent charge recombination between the oxidized dye and the injected electron follows log-normal kinetics.

Free Research Field

物理化学