TY  - JOUR
A1  - Würfel, Uli
A1  - Neher, Dieter
A1  - Spies, Annika
A1  - Albrecht, Steve
T1  - Impact of charge transport on current-voltage characteristics and power-conversion efficiency of organic solar cells
T2  - Nature Communications
N2  - This work elucidates the impact of charge transport on the photovoltaic properties of organic solar cells. Here we show that the analysis of current-voltage curves of organic solar cells under illumination with the Shockley equation results in values for ideality factor, photo-current and parallel resistance, which lack physical meaning. Drift-diffusion simulations for a wide range of charge-carrier mobilities and illumination intensities reveal significant carrier accumulation caused by poor transport properties, which is not included in the Shockley equation. As a consequence, the separation of the quasi Fermi levels in the organic photoactive layer (internal voltage) differs substantially from the external voltage for almost all conditions. We present a new analytical model, which considers carrier transport explicitly. The model shows excellent agreement with full drift-diffusion simulations over a wide range of mobilities and illumination intensities, making it suitable for realistic efficiency predictions for organic solar cells.
Y1  - 2015
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/39032
SN  - 2041-1723
VL  - 6
PB  - Nature Publ. Group
CY  - London
ER  -