Preparation and Photophysical Property of Organized Molecular Assemblies Having Light Energy Conversion Functionalities

2015 Fiscal Year Final Research Report

• Project/Area Number: 26620159
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Energy-related chemistry
• Research Institution: Keio University
• Principal Investigator: Hasobe Taku 慶應義塾大学, 理工学部, 准教授 (70418698)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 分子集合体 / 光エネルギー変換

Outline of Final Research Achievements

Charge-transfer (CT) π-complexes are formed between planar porphyrins and 1,4,5,8,9,12-hexaazatriphenylene (HAT) derivatives with large formation constants, exhibiting broad CT absorption bands. The unusually large formation constants result from close face-to-face contact between two planar π-planes of porphyrins and HAT derivatives. The redox potentials of porphyrins and HAT derivatives measured by cyclic voltammetry indicate that porphyrins and HAT derivatives act as electron donors and acceptors, respectively. Formation of 1 : 1 CT complexes between porphyrins and HAT derivatives was examined by the UV-vis, fluorescence and 1H NMR measurements in nonpolar solvents. The occurrence of unprecedented ultrafast photoinduced electron transfer from the porphyrin unit to the HAT unit in the CT π-complex was observed by femtosecond laser flash photolysis measurements. Highly linear aggregate composed of a planar porphyrin and an HAT derivative was observed by TEM and AFM.

Free Research Field

超分子化学