TY  - JOUR
A1  - Würfel, Uli
A1  - Perdigon-Toro, Lorena
A1  - Kurpiers, Jona
A1  - Wolff, Christian Michael
A1  - Caprioglio, Pietro
A1  - Rech, Jeromy James
A1  - Zhu, Jingshuai
A1  - Zhan, Xiaowei
A1  - You, Wei
A1  - Shoaee, Safa
A1  - Neher, Dieter
A1  - Stolterfoht, Martin
T1  - Recombination between Photogenerated and Electrode-Induced Charges Dominates the Fill Factor Losses in Optimized Organic Solar Cells
JF  - The journal of physical chemistry letters
N2  - Charge extraction in organic solar cells (OSCs) is commonly believed to be limited by bimolecular recombination of photogenerated charges. However, the fill factor of OSCs is usually almost entirely governed by recombination processes that scale with the first order of the light intensity. This linear loss was often interpreted to be a consequence of geminate or trap-assisted recombination. Numerical simulations show that this linear dependence is a direct consequence of the large amount of excess dark charge near the contact. The first-order losses increase with decreasing mobility of minority carriers, and we discuss the impact of several material and device parameters on this loss mechanism. This work highlights that OSCs are especially vulnerable to injected charges as a result of their poor charge transport properties. This implies that dark charges need to be better accounted for when interpreting electro-optical measurements and charge collection based on simple figures of merit.
Y1  - 2019
U6  - https://doi.org/10.1021/acs.jpclett.9b01175
SN  - 1948-7185
VL  - 10
IS  - 12
SP  - 3473
EP  - 3480
PB  - American Chemical Society
CY  - Washington
ER  -