Abstract
Single heterojunction organic photovoltaic cells based on co-evaporated donor-acceptor layers with power conversion efficiencies (η) above 5.5% are demonstrated, using either high (1.8 eV) or low (1.4 eV) optical gap materials. The high energy absorbing cell utilizes a high fullerene-C70 content, in combination with a high mobility amorphous donor, while the low energy absorbing cell consists of a donor-acceptor molecule paired with C60 as the acceptor. The integration of the two cells in an optimized tandem configuration leads to η =7.2%, verified by external quantum efficiency measurements of the subcells. Notably, the fill-factor of the tandem stack is higher than either one of the sub-cells.
Original language | English (US) |
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Article number | 093302 |
Journal | Applied Physics Letters |
Volume | 104 |
Issue number | 9 |
DOIs | |
State | Published - Mar 3 2014 |
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)