Fabrication and physico-chemical properties of Nafion Langmuir-Schaefer films

The Langmuir monolayer behaviour of Nafion (perfluorinated ionomer) films at the air/water interface for different aqueous subphases was investigated. The pressure–area isotherms and the Brewster angle microscopic study of Langmuir monolayer of Nafion in different electrolytic media allowed us to find the best experimental conditions for the deposition of stable Langmuir–Schaefer (LS) films. The results obtained for Nafion LS films through a combination of physical measurements (UV–vis spectroscopy, atomic force microscopy and nano-gravimetry) indicated a stepwise and uniform growth of films on the substrate. The electrochemical and photoelectrochemical properties of dyes incorporated within Nafion LS films were investigated. This paper reports the first experimental results showing the possibility of obtaining and depositing Nafion LS films.