In Situ Characterization of Ultrathin Films by Scanning Electrochemical Impedance Microscopy

Arturo Estrada-Vargas, Aliaksandr Bandarenka, Volodymyr Kuznetsov, Wolfgang Schuhmann

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

Control over the properties of ultrathin films plays a crucial role in many fields of science and technology. Although nondestructive optical and electrical methods have multiple advantages for local surface characterization, their applicability is very limited if the surface is in contact with an electrolyte solution. Local electrochemical methods, e.g., scanning electrochemical microscopy (SECM), cannot be used as a robust alternative yet because their methodological aspects are not sufficiently developed with respect to these systems. The recently proposed scanning electrochemical impedance microscopy (SEIM) can efficiently elucidate many key properties of the solid/liquid interface such as charge transfer resistance or interfacial capacitance. However, many fundamental aspects related to SEIM application still remain unclear. In this work, a methodology for the interpretation of SEIM data of "charge blocking systems" has been elaborated with the help of finite element simulations in combination with experimental results. As a proof of concept, the local film thickness has been visualized using model systems at various tip-to-sample separations. Namely, anodized aluminum oxide (Al2O3, 2-20 nm) and self-assembled monolayers based on 11-mercapto-1-undecanol and 16-mercapto-1-hexadecanethiol (2.1 and 2.9 nm, respectively) were used as model systems. (Figure Presented).

Original languageEnglish
Pages (from-to)3354-3362
Number of pages9
JournalAnalytical Chemistry
Volume88
Issue number6
DOIs
StatePublished - 15 Mar 2016

Fingerprint

Dive into the research topics of 'In Situ Characterization of Ultrathin Films by Scanning Electrochemical Impedance Microscopy'. Together they form a unique fingerprint.

Cite this