Title Enhanced photocurrent spectral response in low-bandgap polyfluorene and C<sub>70</sub>-Derivative-Based Solar Cells Article in journal Authors Xiangjun Wang, Erik Perzon, Frédéric Oswald, Fernando Langa, Shimelis Admassie, Mats R. Andersson, Olle Inganäs Publication Year 2005 Source Advanced Functional Materials, 2005, (15)10, 1665-1670 Link to Source (DOI) 10.1002/adfm.200500114 Abstract <p>Plastic solar cells have been fabricated using a low-bandgap alternating copolymer of fluorene and a donor-acceptor-donor moiety (APFO-Green1), blended with 3<img src="http://www3.interscience.wiley.com/giflibrary/12/prime.gif" />-(3,5-bis-trifluoromethylphenyl)-1<img src="http://www3.interscience.wiley.com/giflibrary/12/prime.gif" />-(4-nitrophenyl)pyrazolino[70]fullerene (BTPF70) as electron acceptor. The polymer shows optical absorption in two wavelength ranges, <img src="http://www3.interscience.wiley.com/giflibrary/12/lambda.gif" /> < 500 nm and 600 < <img src="http://www3.interscience.wiley.com/giflibrary/12/lambda.gif" /> < 1000 nm. The BTPF70 absorbs light at <img src="http://www3.interscience.wiley.com/giflibrary/12/lambda.gif" /> < 700 nm. A broad photocurrent spectral response in the wavelength range 300 < <img src="http://www3.interscience.wiley.com/giflibrary/12/lambda.gif" /> < 1000 nm is obtained in solar cells. A photocurrent density of 3.4 mA cm<sup>-2</sup>, open-circuit voltage of 0.58 V, and power-conversion efficiency of 0.7 % are achieved under illumination of AM1.5 (1000 W m<sup>-2</sup>) from a solar simulator. Synthesis of BTPF70 is presented. Photoluminescence quenching and electrochemical studies are used to discuss photoinduced charge transfer.</p> |