2001 Fiscal Year Final Research Report Summary

Antenna Effects of Dendric Mjultichromophore Arrays and Photochemical Tandem Reaction

Research Project

Project/Area Number	11223204
Research Category	Grant-in-Aid for Scientific Research on Priority Areas (B)
Allocation Type	Single-year Grants
Review Section	Science and Engineering
Research Institution	UNIVERSITY OF TOKYO
Principal Investigator	AIDA Takuzo University of Tokyo, Grad. School of Eng., Prof., 大学院・工学系研究科, 教授 (00167769)
Project Period (FY)	1999 – 2001
Keywords	Dendrimer / Porphyrin / Light-Harvesting Antenna / Artificial Photosynthesis / Energy Migration
Research Abstract	The following information was obtained through researches in three years. 1 Excitation energy absorbed at peripheral aromatic groups was transmitted to the porphyrin at the center of the dendrimer in 80% of the high efficiency. The efficiency decreased to less than 30% of the globular dendrimer when the morphology of the dendrimer was non-globular. High-speed migration of excitation energy between dendrons was suggested from the measurement of fluorescence anisotropy. The energy of visible light absorbed into the dendrimers composed from porphyrins also transferred to the focal point more than 70%. Similar conclusion as 1 was obtained from the morphology dependency of the energy transfer efficiency and the measurement of fluorescence anisotropy. One of the general guidelines for highly efficient energy funneling was the design of spherical orientation of photofunctional molecules and the high utility of dendrimers was demonstrated.