Nanocomposites and nanomaterials

Electrochromic and gas-chromic properties of conjugated polymer films doped with nanoclusters on flexible substrates
Horbenko Yu.Yu1, Aksimentyeva O.I.1, Starykov H.O.1, Ivaniuk K.B.2
1 Ivan Franko National University of Lviv, Kyryla &Mefodia str., 6/8, Lviv 79005, Ukraine. E-mail: yuliia.horbenko@lnu.edu.ua
2 Lviv Polytechnic National University, Bandera str., 12, Lviv 79013, Ukraine.

Due to the development of organic electronics, studies related to the production of thin polymer layers with different functions, such as electrical conductivity, sensory sensitivity, absorption or emitting light in a fixed optical range, become particularly relevant. Such coatings can be obtained by simple non-vacuum methods, including polymerization on solid surfaces. One of the main advantages of this approach is the ability to obtain functional materials directly on polymer substrates, which is important for the production of flexible screens, organic LEDs, and electrochromic devices [1, 2].
In this research, the methods of formation of conjugated polymers films – polyaniline, poly-ortho-anisidine (PoA), and poly-3,4-ethylenedioxythiophene, and their doping by nanoclusters of K3[Fe(CN)6], graphene oxide, etc. were optimized. Samples were obtained by electrochemical deposition of polymers on transparent flexible substrates of polyethyleneterephthalate (PET) with a conductive layer of Indium tin oxide (ITO). The impact of the electric field on the changes in the optical absorption spectra of the polymer films and their electrochromic characteristics were studied. It was established that the most significant changes in the optical characteristics of PoA (76%) were observed in polymer electrolyte based on PVA and lithium perchlorate at λ = 650 nm when the potential switch from -0.2 to +0.6 V (Ag/AgCl). Moreover, the influence of gas vapors of various nature on the film’s absorption spectra was investigated. The results will be the basis for further development of the method of functional polymer layer formation for flexible optoelectronic devices and optical sensors for the selective detection of harmful vapors in industry and the environment.

1.	Park Y., Bormann L., Müller-Meskamp L., et al. Efficient flexible organic photovoltaics using silver nanowires and polymer based transparent electrodes // Org. Electron.-2016.-36.-P.68-72.
2.	Aksymentyeva O., Zayarnyuk T., Konopelnyk O., et al. Effect of doping on thermo-optical behavior of poly-3,4ethylenedioxythiophene films // Visnyk of the Lviv University. Ser. Chem.-2016.-57.-P.432-439.