One of the parameters that limit the performance of polymer solar cells is the mismatch between the absorption spectrum of the photoactive layer and the solar emission. We report a series of low band gap conjugated polymers that may alleviate this problem. Conjugated polymers with optical band gaps ranging from 1.8 eV down to 1.2 eV (>1000 nm) will be presented. The high mol. wt. materials can be processed from soln. Photovoltaic cells of the polymers in bulk-heterojunctions with fullerene (PCBM), provide spectral responses into the near IR, corresponding to the absorption spectra. The overall power conversion efficiency of the devices with the lowest band gaps (1.2 eV) is estd. at ca. 1% under AM1.5 and is mainly limited by a low photocurrent, rather than by the fill factor (up to 0.6) or open circuit voltage (up to 0.6 V).
|Titel||Abstracts of Papers, 232nd ACS National Meeting, San Francisco, CA, United States, Sept. 10-14, 2006|
|Plaats van productie||Washington, D. C|
|Uitgeverij||American Chemical Society|
|Status||Gepubliceerd - 2006|