Electron-induced modification of self-assembled monolayers of aromatic carboxylic acids

• Verfasst von: Asyuda, Andika [VerfasserIn]
• Verfasst von: Ortiz de la Morena, Rodrigo [VerfasserIn]
• Verfasst von: Sauter, Eric [VerfasserIn]
• Verfasst von: Turner, Kelly [VerfasserIn]
• Verfasst von: McDonald, Kirsty [VerfasserIn]
• Verfasst von: Buck, Manfred [VerfasserIn]
• Verfasst von: Zharnikov, Michael [VerfasserIn]
• Titel: Electron-induced modification of self-assembled monolayers of aromatic carboxylic acids
• Verf.angabe: Andika Asyuda, Rodrigo Ortiz de la Morena, Eric Sauter, Kelly Turner, Kirsty McDonald, Manfred Buck, and Michael Zharnikov
• E-Jahr: 2020
• Jahr: October 30, 2020
• Umfang: 14 S.
• Fussnoten: Gesehen am 17.02.2022
• Titel Quelle: Enthalten in: The journal of physical chemistry <Washington, DC> / C
• Ort Quelle: Washington, DC : Soc., 2007
• Jahr Quelle: 2020
• Band/Heft Quelle: 124(2020), 45, Seite 25107-25120
• ISSN Quelle: 1932-7455
• DOI: doi:10.1021/acs.jpcc.0c07577
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 178951939X

Abstract

The effects of low-energy electrons on aromatic self-assembled monolayers (SAMs) with carboxylic acid (CA) docking groups were studied with a focus on the dose range below 5 mC/cm2. The SAMs were prepared on an underpotentially deposited Ag bilayer and comprised nonsubstituted and CA-substituted monolayers with a rod-like biphenyl backbone and a monolayer of a Y-shaped, CA-substituted molecule, 1,3,5-benzenetribenzoic acid (H3BTB), formed either as a single-component film or as a binary one by mixing with adamantane-CA (Ad-CA). X-ray photoelectron and near-edge X-ray absorption fine structure spectra suggest high proneness of the CA groups to electron irradiation at both SAM/substrate and SAM/ambient interfaces. Cleavage of the carboxylate-substrate bond results in substantial molecular desorption at the initial stage of irradiation until electron-induced cross-linking gradually takes over. The CA groups at the outer SAM interface undergo substantial chemical changes, indicating that they participate in the cross-linking chemistry. The electron-induced processes are accompanied by molecular reorientation. Disordering for the SAMs formed by the rod-like molecules is contrasted by the H3BTB-based systems where changes also occur but some molecular order is preserved as explained by a proposed model invoking conformational changes. In SAMs of H3BTB mixed with Ad-CA, the latter shows higher proneness to irradiation-induced desorption than the former, as well as an influence on the cross-linking chemistry. The results of the present study suggest that CA-based SAMs on Ag offer additional options for cross-linking in SAMs and, as exemplarily demonstrated by the generation of Cu patterns on structured H3BTB templates, can be efficiently used for lithography and nanofabrication