Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy

Korolkov, Vladimir V.; Summerfield, Alex; Murphy, Alanna; Amabilino, David B.; Watanabe, Kenji; Taniguchi, Takashi; Beton, Peter H.

Abstract

Real-space images of polymers with sub-molecular resolution could provide valuable insights into the relationship between morphology and functionality of polymer optoelectronic devices, but their acquisition is problematic due to perceived limitations in atomic force microscopy (AFM). We show that individual thiophene units and the lattice of semicrystalline spin-coated films of polythiophenes (PTs) may be resolved using AFM under ambient conditions through the low-amplitude (≤ 1 nm) excitation of higher eigenmodes of a cantilever. PT strands are adsorbed on hexagonal boron nitride near-parallel to the surface in islands with lateral dimensions ~10 nm. On the surface of a spin-coated PT thin film, in which the thiophene groups are perpendicular to the interface, we resolve terminal CH3-groups in a square arrangement with a lattice constant 0.55 nm from which we can identify abrupt boundaries and also regions with more slowly varying disorder, which allow comparison with proposed models of PT domains.

Citation

Korolkov, V. V., Summerfield, A., Murphy, A., Amabilino, D. B., Watanabe, K., Taniguchi, T., & Beton, P. H. (2019). Ultra-high resolution imaging of thin films and single strands of polythiophene using atomic force microscopy. Nature Communications, 10, Article 1537. https://doi.org/10.1038/s41467-019-09571-6

• Journal Article Type: Article
• Acceptance Date: Mar 6, 2019
• Online Publication Date: Apr 4, 2019
• Publication Date: Apr 4, 2019
• Deposit Date: Mar 20, 2019
• Publicly Available Date: Apr 5, 2019
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Article Number: 1537
• DOI: https://doi.org/10.1038/s41467-019-09571-6
• Keywords: General Biochemistry, Genetics and Molecular Biology; General Physics and Astronomy; General Chemistry
• Public URL: https://nottingham-repository.worktribe.com/output/1670667
• Publisher URL: https://www.nature.com/articles/s41467-019-09571-6