Conducting Polymers
The Department concentrates on the preparation of conducting polymers, such as polyaniline, polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), etc., by the chemical oxidative or electrochemical polymerizations of corresponding monomers. The control of polymer morphology, viz. the formation of one-dimensional nanostructures, and high electrical conductivity is the main goal. The preparation of hybrid composites composed of conducting polymers and organic or inorganic components offers the route to the preparation of new materials. Furthermore, the applications of such conducting materials as electrodes in supercapacitors and adsorbents for pollutants from wastewater are investigated.
International research team is composed of 5 researchers, 3 PhD students, and technicians.
Research scope
Synthesis of conducting polymers and their composites
Conducting polymers can be obtained in various forms (Fig. 1). 
Powders are typically produced when oxidation of monomer is carried out in acidic aqueous medium. Thin polymer films are deposited on any surface immersed in the reaction mixture or can be prepared electrochemically. Hybrid composites are produced by coating of various inorganic and organic objects with conducting polymers (e.g., transition metal dichalcogenide, ferrites, cotton textile, or metal-organic framework). Colloidal dispersions are obtained if a water-soluble polymer stabilizer is present in the reaction mixture. When the polymerization of monomers is carried out in the presence of water-soluble polymers in a frozen reaction mixture, soft conducting hydrogels are obtained after thawing. Aerogels can be obtained by freeze-drying of hydrogel or solvent-exchange technique. Recently, the main focus is concentrated on the improvement of PPy conductivity by modification of synthesis route, by the addition of organic dyes into pyrrole polymerization. The highest conductivity of 175 S cm–1 was achieved when PPy nanorods were prepared in the presence of safranin at −24 °C. Morphology-retaining carbonization of conducting polymers is the way to produce new nitrogen-rich carbonaceous materials with high specific surface area and defined morphology.
|
|
|
|
|
|
|
|
|
|
|
|
Electrochemical characterization
The electrochemical methods, like cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy, electrochemical quartz-crystal micro-balance, and spectro-electrochemical measurements, are used to study electrochemical performance of conducting polymers. Recently, they have been applied to understand the role of H-bonds on the morphology, structure, and electrochemical performance of the PEDOT. The formation of cation radicals in PEDOT was shown to be induced by H-bond formation between formic acid and polymer. PEDOT chains can undergo rearrangements under electrochemical performance with the formation of an anisotropic structure, which was confirmed by polarized microscopy.
|
|
|
|
|
|
|
|
Applications
The synthesized conducting polymers and their composites are applied:
- As sensing layers in bio-sensor applications for earlier detection of infection and bacterial colonization.
- In controlled adsorption and photocatalytic decomposition of water contaminants, like dyes, drugs, and heavy-metal ions. The adsorption process can be monitored by UV-Vis spectroscopy.
- As functional materials in energy and electronic applications.
|
|
|
|
|
|
|
|
|
|
|
|
Funding Support
- Czech Health Research Council (NU20-06-00424): Implantable sensors for early detection of infection and bacterial colonization
(2019–2023). - Czech Science Foundation (21-01401S): Innovative conducting polymer composites for water purification (2021–2024).
- M-ERA.NET - The Technology Agency of the Czech Republic (TH80020001): Development of novel Li ion battery solid electrolyte separators based on metal organic frameworks (2022-2025).
Patents and utility models
- P. Bober, F. Josefík, L. Kubáč, L. Martinková, J. Marek, Funkční vodivá flexibilní textilie s antistatickými a nehořlavými vlastnostmi, 2019, 33188.
- F. Josefík, L. Kubáč, J. Černý, P. Bober, L. Martinková, J. Marek, Funkční vodivá textilie s disipativními, antistatickými a antimikrobiálními vlastnostmi, 2019, 33415.
- L. Brožová, E. Tomšík, J. Žitka, Composite membranes for separation of gas mixtures and a method of preparation thereof, 2018, EP2858739-B1.