Impact of interfacial molecular orientation on radiative recombination and charge generation efficiency

Niva A. Ran, Steffen Roland, John A. Love, Victoria Savikhin, Christopher J. Takacs, Yao Tsung Fu, Hong Li, Veaceslav Coropceanu, Xiaofeng Liu, Jean Luc Brédas, Guillermo C. Bazan, Michael F. Toney, DIeter Neher, Thuc Quyen Nguyen*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

208 Scopus citations

Abstract

A long standing question in organic electronics concerns the effects of molecular orientation at donor/acceptor heterojunctions. Given a well-controlled donor/acceptor bilayer system, we uncover the genuine effects of molecular orientation on charge generation and recombination. These effects are studied through the point of view of photovoltaics-however, the results have important implications on the operation of all optoelectronic devices with donor/acceptor interfaces, such as light emitting diodes and photodetectors. Our findings can be summarized by two points. First, devices with donor molecules face-on to the acceptor interface have a higher charge transfer state energy and less non-radiative recombination, resulting in larger open-circuit voltages and higher radiative efficiencies. Second, devices with donor molecules edge-on to the acceptor interface are more efficient at charge generation, attributed to smaller electronic coupling between the charge transfer states and the ground state, and lower activation energy for charge generation.

Original languageEnglish (US)
Article number79
JournalNature Communications
Volume8
Issue number1
DOIs
StatePublished - Dec 1 2017
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2017 The Author(s).

ASJC Scopus subject areas

  • General Chemistry
  • General Biochemistry, Genetics and Molecular Biology
  • General Physics and Astronomy

Fingerprint

Dive into the research topics of 'Impact of interfacial molecular orientation on radiative recombination and charge generation efficiency'. Together they form a unique fingerprint.

Cite this