Chemical modification of gold surface via UV-generated aryl radicals derived 3,5-bis(trifluoromethyl)phenyl)iodonium salt

• Published in: Progress in organic coatings Vol. 136; p. 105211
• Main Authors: Guselnikova, O., Miliutina, E., Elashnikov, R., Burtsev, V., Chehimi, M.M., Svorcik, V., Yusubov, M., Lyutakov, O., Postnikov, P.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.11.2019; Elsevier BV
• Subjects: Aromatic compounds; Bonding strength; Control surfaces; Ellipsometry; Functional groups; Iodonium salts; Organic chemistry; Organic layers; Photocatalysis; Photoinitiators; Radicals; Raman spectroscopy; Surface modification; Surface patterning; Thickness; Ultraviolet radiation; Wettability; X ray photoelectron spectroscopy; Surface modification; Surface patterning; Iodonium salts; Organic layers; Photocatalysis
• ISSN: 0300-9440; 1873-331X
• DOI: 10.1016/j.porgcoat.2019.105211

•The generation of active aryl radicals under UV-light without application of photoinitiators from iodonium salts (IS) have been demonstrated.•The convenient one-step procedure for the surface modification of gold surface by IS under UV-light irradiation have been proposed.•The formation of close-to-monolayer organic coating on the gold films have been demonstrated.•The possibility of surface patterning by organic functional groups using iodonium salts have been proposed. In recent years, iodonium salts emerged as a unique novel class of compounds for surface modification by electrografting. Herein, we demonstrated that 3,5-bis(trifluoromethyl)phenyl)iodonium salt (IS-(CF3)2) can be applied for the modification of surfaces via generation of aryl radicals through activation by UV light, without the addition of any photoinitiators. The thickness of the organic layer was found to be close to the size of an organic radical. The as-prepared structures were characterized by XPS, wettability, Raman spectroscopy and AFM measurements. The formation of close to monomolecular layer on the surface was proved by three independent methods (AFM, XPS, and ellipsometry). UV-generated aryl radicals can also be used for simple one-step surface patterning with organic functional groups. In our contribution, we developed a convenient and easy-to-handle approach for the grafting of modified patterns. The application of IS-(CF3)2 allows controlling the distribution of surface-modified area via the application of the lithographic mask. The proposed strategy offers advantages such as strong covalent bonding of aryl radical, easiness of experimental procedure in combination with the possibility to control surface architecture.