Diketopyrrolopyrroles as Acceptor Materials in Organic Photovoltaics

• Published in: Macromolecular rapid communications 2010-09, Vol.31 (17), p.1554-1559
• Main Authors: Karsten, Bram P., Bijleveld, Johan C., Janssen, René A. J.
• Format: Article
• Language: English
• Subjects: Acceptor materials; Application fields; Applied sciences; conjugated polymers; Conversion; Derivatives; Devices; diketopyrrolopyrroles; Energy; Exact sciences and technology; n-type materials; Natural energy; oligomers; Photovoltaic cells; Photovoltaic conversion; Polymer industry, paints, wood; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Solar power generation; Technology of polymers; Wavelengths
• ISSN: 1022-1336; 1521-3927; 1521-3927
• DOI: 10.1002/marc.201000133

In the search of new electron acceptor, n‐type materials for organic solar cells that combine a strong absorption over a broad range with good electrical characteristics, the use of diketopyrrolopyrrole (DPP) derivatives with low reduction potentials is explored. A series of small molecule DPP derivatives is presented and the compounds are tested as electron acceptors in combination with poly(3‐hexylthiophene) (P3HT) as the donor material. Working photovoltaic devices are obtained that show a photoresponse in the wavelength region where the DPP molecules absorb. The best device shows a power conversion efficiency of 0.31% in simulated solar light, with a photon‐to‐electron conversion efficiency of ∼10% up to 700 nm. The efficiency seems to be limited by the coarse morphology of the blend. Diketopyrrolopyrroles (DPPs) are explored in the search of new electron acceptor materials for organic solar cells. DPPs have already been successfully used as donor materials, but also have low reduction potentials and significant electron mobilities. A series of small DPP molecules is presented and the compounds are tested as electron acceptors, in combination with polythiophene as a donor, in organic solar cells. The best device shows an efficiency of 0.31%.