Energy-Level Modulation of Small-Molecule Electron Acceptors to Achieve over 12% Efficiency in Polymer Solar Cells

Sunsun Li; Long Ye; Wenchao Zhao; Shaoqing Zhang; Subhrangsu Mukherjee; Harald Ade; Jianhui Hou

doi:10.1002/adma.201602776

Energy-Level Modulation of Small-Molecule Electron Acceptors to Achieve over 12% Efficiency in Polymer Solar Cells

Adv Mater. 2016 Nov;28(42):9423-9429. doi: 10.1002/adma.201602776. Epub 2016 Sep 8.

Authors

Sunsun Li^{1

2}, Long Ye³, Wenchao Zhao^{1

2}, Shaoqing Zhang¹, Subhrangsu Mukherjee³, Harald Ade³, Jianhui Hou^{1

2}

Affiliations

¹ State Key Laboratory of Polymer Physics and Chemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
² University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
³ Department of Physics and Organic and Carbon Electronics Lab (ORaCEL), North Carolina State University, Raleigh, NC, 27695, USA.

PMID: 27606970
DOI: 10.1002/adma.201602776

Abstract

Fine energy-level modulations of small-molecule acceptors (SMAs) are realized via subtle chemical modifications on strong electron-withdrawing end-groups. The two new SMAs (IT-M and IT-DM) end-capped by methyl-modified dicycanovinylindan-1-one exhibit upshifted lowest unoccupied molecular orbital (LUMO) levels, and hence higher open-circuit voltages can be observed in the corresponding devices. Finally, a top power conversion efficiency of 12.05% is achieved.

Keywords: end-groups; energy-level modulation; nonfullerene acceptors; polymer solar cells; soft X-ray scattering.