Fluorescence and Electroluminescence of J-Aggregated Polythiophene Monolayers on Hexagonal Boron Nitride

Kerfoot, James; Svatek, Simon A.; Korolkov, Vladimir V.; Taniguchi, Takashi; Watanabe, Kenji; Antolin, Elisa; Beton, Peter H.

Abstract

The photophysics of a semiconducting polymer is manipulated through molecular self-assembly on an insulating surface. Adsorption of polythiophene (PT) monolayers on hexagonal boron nitride (hBN) leads to a structurally induced planarization and a rebalancing of inter- and intrachain excitonic coupling. This conformational control results in a dominant 0–0 photoluminescence peak and a reduced Huang–Rhys factor, characteristic of J-type aggregates, and optical properties which are significantly different to both PT thin films and single polymer strands. Adsorption on hBN also provides a route to explore electroluminescence from PT monolayers though incorporation into hybrid van der Waals heterostructures whereby the polymer monolayer is embedded within a hBN tunnel diode. In these structures we observe up-converted singlet electroluminescence from the PT monolayer, with an excitation mechanism based upon inelastic electron scattering. We argue that surface adsorption provides a methodology for the study of fundamental optoelectronic properties of technologically relevant polymers.

Citation

Kerfoot, J., Svatek, S. A., Korolkov, V. V., Taniguchi, T., Watanabe, K., Antolin, E., & Beton, P. H. (2020). Fluorescence and Electroluminescence of J-Aggregated Polythiophene Monolayers on Hexagonal Boron Nitride. ACS Nano, 14(10), 13886–13893. https://doi.org/10.1021/acsnano.0c06280

• Journal Article Type: Article
• Acceptance Date: Sep 8, 2020
• Online Publication Date: Sep 11, 2020
• Publication Date: Oct 27, 2020
• Deposit Date: Sep 14, 2020
• Publicly Available Date: Sep 12, 2021
• Journal: ACS Nano
• Print ISSN: 1936-0851
• Electronic ISSN: 1936-086X
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 14
• Issue: 10
• Pages: 13886–13893
• DOI: https://doi.org/10.1021/acsnano.0c06280
• Keywords: General Engineering; General Physics and Astronomy; General Materials Science
• Public URL: https://nottingham-repository.worktribe.com/output/4901557
• Publisher URL: https://pubs.acs.org/doi/10.1021/acsnano.0c06280