The nature of self-assembled octadecylphosphonic acid (ODPA) layers on copper substrates

Zhao W, Göthelid M, Hosseinpour S, Johansson MB, Li G, Leygraf C, Johnson CM (2021)

Publication Type: Journal article

Publication year: 2021

Journal

Journal of Colloid and Interface Science Elsevier

Book Volume: 581

Pages Range: 816-825

DOI: 10.1016/j.jcis.2020.07.058

Abstract

Hypothesis: The self-assembly of amphiphilic molecules onto solid substrates can result both in the formation of monolayers and multilayers. However, on oxidized and non-oxidized copper (Cu), only monolayer formation was reported for phosphonic acids possessing one phosphate head group. Here, the adsorption of octadecylphosphonic acid (ODPA) on Cu substrates through a self-assembly process was investigated with the initial hypothesis of monolayer formation. Experiments: The relative amount of ODPA adsorbed on a Cu substrate was determined by infrared reflection/absorption spectroscopy (IRRAS) and by atomic force microscopy (AFM) investigations before and after ODPA deposition. X-ray photoelectron spectroscopy (XPS) with sputtering was used to characterize the nature of the layers. Findings: The results show that the thickness of the ODPA layer increased with deposition time, and after 1 h a multilayer film with a thickness of some tens of nm was formed. The film was robust and required long-time sonication for removal. The origin of the film robustness was attributed to the release of Cu ions, resulting in the formation of Cu-ODPA complexes with Cu ions in the form of Cu(I). Preadsorbing a monolayer of octadecylthiol (ODT) onto the Cu resulted in no ODPA adsorption, since the release of Cu(I) ions was abolished.

Authors with CRIS profile

Saman Hosseinpour Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik

Involved external institutions

Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH) SE Sweden (SE) Uppsala University SE Sweden (SE)

How to cite

APA:

Zhao, W., Göthelid, M., Hosseinpour, S., Johansson, M.B., Li, G., Leygraf, C., & Johnson, C.M. (2021). The nature of self-assembled octadecylphosphonic acid (ODPA) layers on copper substrates. Journal of Colloid and Interface Science, 581, 816-825. https://dx.doi.org/10.1016/j.jcis.2020.07.058

MLA:

Zhao, Weijie, et al. "The nature of self-assembled octadecylphosphonic acid (ODPA) layers on copper substrates." Journal of Colloid and Interface Science 581 (2021): 816-825.

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