@misc{DrexlerShishkanovaLangeetal., author = {Drexler, Christoph and Shishkanova, Tatiana V. and Lange, Christoph and Danilov, Sergey N. and Weiss, Dieter and Ganichev, Sergey D. and Mirsky, Vladimir M.}, title = {Terahertz split-ring metamaterials as transducers for chemical sensors based on conducting polymers: a feasibility study with sensing of acidic and basic gases using polyaniline chemosensitive layer}, series = {Microchimica Acta}, volume = {181}, journal = {Microchimica Acta}, issn = {1436-5073}, doi = {10.5283/epub.31493}, pages = {1857 -- 1862}, abstract = {We report on the first application of terahertz metamaterials acting as transducers for chemical sensors based on conducting polymers. In our feasibility study aimed at sensing of gaseous hydrochloric and ammonia, a two-dimensional sensor metamaterial consisting of an array of split-ring resonators on the surface of undoped silicon wafer was prepared. The surface of the resonator was coated with a 150-μm layer of polyaniline. Binding of hydrogen chloride to polyaniline leads to distinct changes in the resonance frequency of the metamaterial. Measurements can be performed both in the reflection and transmission mode. A numerical simulation of the response revealed an increase of both the real and the imaginary components of the dielectric function of the polyaniline film. These changes are attributed to the transition from emaraldine base to emeraldine salt. The results demonstrate a new approach for formation of highly sensitive transducers for chemical sensors.}, language = {en} } @misc{ShishkanovaHavlikKraletal., author = {Shishkanova, Tatiana V. and Havlik, Martin and Kr{\´a}l, Vladim{\´i}r and Kopeck{\´y}, Dušan and Matějka, Pavel and Dendisov{\´a}, Marcela and Mirsky, Vladimir M.}, title = {Amino-substituted Tr{\"o}ger's base: electrochemical polymerization and characterization of the polymer film}, series = {Electrochimica Acta}, volume = {224}, journal = {Electrochimica Acta}, issn = {0013-4686}, doi = {10.1016/j.electacta.2016.12.061}, pages = {439 -- 445}, abstract = {The amino-substituted coumarin derivative of Tr{\"o}ger's base (CTB) was electrochemically polymerized on the surface of gold electrodes. The obtained polymer films were characterized by SEM, Raman spectroscopy, cyclic voltammetry and in-situ conductometry. Spectroscopic analysis indicates that the polymerization of CTB takes place via oxidation of the aniline fragment of CTB molecule, similar to the polymerization of aniline. The similarity of the polymer backbone to that of the polyaniline is also confirmed by the influence of potential on the film's conductivity, however the conductivity of the new material is in principle lower than that of polyaniline. SEM shows that the polymer forms a thin layer with a thickness of ~ 100 nm. Possible applications of the new material as an artificial receptor for aromatic analytes containing carboxy-group are proposed.}, language = {en} }