Fullerene-free polymer solar cells with strongly reduced bimolecular recombination and field- independent charge carrier generation

Published

August 21, 2014

Author(s)

Steffen Roland, Marcel Schubert, Brian A. Collins, Jona Kurpiers, Zhihua Chen, Antonio Facchetti, Harald Ade, Dieter Neher

Abstract

Photogeneration, recombination and transport of free charge carriers in all-polymer bulk heterojunction solar cells incorporating P3HT as donor and P(NDI2OD-T2) as acceptor polymer have been investigated by the use of time delayed collection field (TDCF) and time of flight (TOF) measurements. Depending on the preparation procedure used to dry the active layers, these solar cells comprise high fill factors (FF) of up to 67%. A strongly reduced bimolecular recombination (BMR) in combination with field-independent free charge carrier generation are observed, features that are common to high performance fullerene-based solar cells. Resonant soft x-ray measurements (R-SoXs) and photoluminescence quenching experiments (PQE) reveal that the BMR is related to domain purity . Our results elucidate the similarities of polymeric acceptors with the superior recombination properties of fullerene acceptors.

Citation

Journal of Physical Chemistry Letters

Pub Type

Journals

Keywords

All-polymer solar cells, organic solar cells, photocurrent generation, bimolecular recombination, reduced recombination, domain purity

Citation

Roland, S. , Schubert, M. , Collins, B. , Kurpiers, J. , Chen, Z. , Facchetti, A. , Ade, H. and Neher, D. (2014), Fullerene-free polymer solar cells with strongly reduced bimolecular recombination and field- independent charge carrier generation, Journal of Physical Chemistry Letters (Accessed October 11, 2025)