π-Bridge-Independent 2-(Benzo[c][1,2,5]thiadiazol-4-ylmethylene)malononitrile-Substituted Nonfullerene Acceptors for Efficient Solar Cells

Kai Wang, Yuliar Firdaus, Maxime Babics, Federico Cruciani, Qasim Saleem, Abdulrahman El Labban, Maha A Alamoudi, Tomasz Marszalek, Wojciech Pisula, Frédéric Laquai, Pierre Beaujuge

Research output: Contribution to journalArticlepeer-review

99 Scopus citations

Abstract

Molecular acceptors are promising alternatives to fullerenes (e.g. PC61/71BM) in the fabrication of high-efficiency bulk-heterojunction (BHJ) solar cells. While solution-processed polymer-fullerene BHJ devices have recently met the 10% efficiency threshold, molecular acceptors have yet to prove comparably efficient with polymer donors. At this point in time, it is important to forge a better understanding of the design parameters that directly impact small-molecule (SM) acceptor performance in BHJ solar cells. In this report, we show that 2-(benzo[c][1,2,5]thiadiazol-4-ylmethylene)malononitrile (BM)-terminated SM acceptors can achieve efficiencies as high as 5.3% in BHJ solar cells with the polymer donor PCE10. Through systematic device optimization and characterization studies, we find that the nonfull-erene analogues (FBM, CBM and CDTBM) all perform comparably well, independent of the molecular structure and electronics of the π-bridge that links the two electron-deficient BM end groups. With estimated electron affinities within range of those of common fullerenes (4.0-4.3 eV), and a wider range of ionization potentials (6.2-5.6 eV), the SM acceptors absorb in the visible spectrum and effectively contribute to the BHJ device photocurrent. BM-substituted SM acceptors are promising alterna-tives to fullerenes in solution-processed BHJ solar cells.
Original languageEnglish (US)
Pages (from-to)2200-2208
Number of pages9
JournalChemistry of Materials
Volume28
Issue number7
DOIs
StatePublished - Mar 28 2016

Bibliographical note

KAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): CRG_R2_13_BEAU_KAUST_1
Acknowledgements: This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No.CRG_R2_13_BEAU_KAUST_1. The authors acknowledge concurrent support under Baseline Research Funding from KAUST. The authors thank KAUST ACL for technical support in the mass spectrometry analyses. W.P. and T.M. gratefully acknowledge the staff of beamline
9 at the DELTA electron storage ring in Dortmund for providing beamtime and technical support for the GIWAXS measurements. W.P. and T.M. thank Marcelina Rojek for technical support in the GIWAXS measurements.

Fingerprint

Dive into the research topics of 'π-Bridge-Independent 2-(Benzo[c][1,2,5]thiadiazol-4-ylmethylene)malononitrile-Substituted Nonfullerene Acceptors for Efficient Solar Cells'. Together they form a unique fingerprint.

Cite this