Charge separation in metallomacrocycle complexes linked with electron acceptors by axial coordination
Shunichi Fukuzumi1, Tatsuhiko Honda, Kei Ohkubo
1Department of Material and Life Science, Division of Advanced Science and Biotechnology, Graduate School of Engineering, Osaka University, SORST, Science and Technology Agency (JST), Suita, Osaka 565-0871, Japan. fukuzumi@chem.eng.osaka-u.ac.jp
Dalton Transactions (Cambridge, England : 2003)
|May 15, 2009
Summary
Researchers created linked donor-acceptor metallomacrocycles for solar cells. Axial coordination bonds and hydrogen bonding enabled the formation of supramolecular assemblies with enhanced charge separation.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Photovoltaics
Background:
- Metallomacrocycle complexes offer a route to precisely control donor-acceptor interactions.
- Axial ligand coordination is a key strategy for constructing well-defined supramolecular architectures.
- Phthalocyanine and porphyrin derivatives are versatile platforms for developing functional materials.
Purpose of the Study:
- To synthesize novel silicon phthalocyanine (SiPc) triads bearing electron acceptors.
- To construct donor-acceptor complexes using zinc porphyrin derivatives and axial coordination.
- To investigate charge separation mechanisms and potential applications in supramolecular solar cells.
Main Methods:
- Synthesis of SiPc-(C(60))(2), SiPc-(TNF)(2), and SiPc-(TNDCF)(2) triads.
- Formation of ZnTPP-PyNIm donor-acceptor complexes via nitrogen coordination.
- Assembly of ZnOPPc and H(4)DPP(2+) using 4-pyridinecarboxylate through axial coordination and hydrogen bonding.
Main Results:
- Successfully synthesized electron acceptor-bearing SiPc triads.
- Demonstrated enhanced binding in Zn-porphyrin complexes through porphyrin ring distortion.
- Achieved discrete supramolecular assemblies with potential for efficient charge separation.
Conclusions:
- Axial coordination to metallomacrocycles is an effective method for creating linked donor-acceptor systems.
- Distorted porphyrin rings enhance binding and facilitate supramolecular assembly.
- These metallomacrocycle-based systems show promise for the development of advanced supramolecular solar cells.
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