Vapor deposition of metal-doped polyaniline coatings, their molecular structure

Abstract

Doping of polyaniline (PANI) coatings by metal nanoparticles is a highly effective method for increasing their electrically conductive (EC), photovoltaic, and catalytic properties. In this case, the particular interest is the formation of metal-filled polyaniline coatings during their synthesis by the vacuum method. The growth of the polymer chain and the processes of structure formation proceed simultaneously and it becomes possible to vary the degree of doping, protonation, and ordering of the formed thin-film systems in a wide range. The purpose of the development is to determine the peculiarities of the formation of electron-beam dispersion from volatile products, the molecular structure of polyaniline-based layers containing noble metal nanoparticles, and to establish the effect of dopants on the molecular organization of the formed layers. The features of deposition from volatile products of electron-beam dispersion of nanocomposite polyaniline-based coatings and metal nanoparticles (silver, gold) are determined. The features of the molecular structure of the layers and the influence and its change upon the introduction of dopants by the methods of Raman and IR Fourier spectroscopy have been established. It is shown that the coatings have a conformational state of macromolecules in the form of flat extended chains, and a more oxidized structure of polyaniline layers is observed when silver chloride is used. It is shown that the features of the molecular structure of the formed polymer matrix based on polyaniline are due to the manifestation of a specific non-covalent interaction of macromolecules with metal nanoparticles. Analysis of the study results indicates the deposition possibility from the gas phase of nanocomposite conducting coatings based on polyaniline, which are a system of protonated conducting polymer chains and metal clusters. Such coatings are promising elements of sensor devices for various purposes; they can be used, in particular, in the creation of electrochromic devices.