Enhancement of Light-Energy Conversion Efficiency by Multi-Porphyrin Arrays of Porphyrin−Peptide Oligomers with Fullerene Clusters

• Published in: The journal of physical chemistry. B 2005-01, Vol.109 (1), p.19-23
• Main Authors: Hasobe, Taku, Kamat, Prashant V., Troiani, Vincent, Solladié, Nathalie, Ahn, Tae Kyu, Kim, Seong Keun, Kim, Dongho, Kongkanand, Anusorn, Kuwabata, Susumu, Fukuzumi, Shunichi
• Format: Article
• Language: English
• Subjects: Electrochemistry; Fullerenes - chemistry; Fullerenes - radiation effects; Light; Molecular Structure; Particle Size; Peptides - chemistry; Peptides - radiation effects; Photochemistry; Porphyrins - chemistry; Porphyrins - radiation effects
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp045246v

Organic photovoltaic cells using supramolecular complexes of porphyrin−peptide oligomers (porphyrin-functionalized α-polypeptides) with fullerene demonstrate remarkable enhancement in the photoelectrochemical performance as well as broader photoresponse in the visible and near-infrared regions by increasing the number of porphyrin units in α-polypeptide structures. A high power conversion efficiency (η) of 1.3% and a maximum incident photon-to-photocurrent efficiency (IPCE) of 42% were attained using composite clusters of porphyrin−peptide octamer and fullerene. These results clearly show that the formation of a molecular assembly between fullerene and multi-porphyrin arrays with a polypeptide backbone controls the electron transfer efficiency in the supramolecular complex, which is essential for the light-energy conversion.