TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Electroanalytical measurements without electrolytes: Conducting polymers as probes for redox titration in non-conductive organic media T2 - Analytica Chimica Acta N2 - Electroanalytical methods have been applied only in conducting media. An application of conducting polymers allows to overcome this limitation. If such material is in electrochemical equilibrium with dissolved redox active species, its electrical conductivity depends on the redox potential of these species. Therefore, conductometric measurements with conducting polymers can provide about the same information as classical redox electrodes. The approach was applied for redox titration. Equivalent points obtained by this titration in aqueous and organic electrolytes were identical. Then the approach was applied for determination of bromine number by redox titration in non-conducting organic phase. KW - Conducting polymers KW - Redox titration KW - Conductometric sensors KW - Non-conductive media Y1 - 2012 U6 - https://doi.org/10.1016/j.aca.2012.07.024 SN - 0003-2670 VL - 744 SP - 29 EP - 32 ER - TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Polythiophene films on gold electrodes: A comparison of bulk and contact resistances in aqueous and organic media T2 - Journal of Solid State Electrochemistry N2 - Recently, developed technique for separated analysis of bulk and contact resistance was applied for the investigation of polythiophene films electropolymerized in boron trifluoride diethylether. Kinetics of polymer resistance and for the first time of the contact resistance during polymer oxidation and reduction were characterized. Influence of electrochemically controlled oxidation state on the polymer bulk and the polymer/metal contact resistance was measured in aqueous and organic environment. Variation of the electrical potential from −0.2 to 1.1 V vs. Ag/AgCl (sat) leads to an increase of the polymer conductivity for about three orders of magnitude and to a decrease of the contact resistance for about three orders of magnitude. The potential dependence of the two resistances was different, especially at high anodic potentials. In organic solution, the change of both resistances was more than six orders of magnitude. The results were compared with electrochemical and spectroelectrochemical data, a difference in the material behavior depending on the electrolyte solvent was observed. The influence of electrical potential on polymer resistance in aqueous solution was explained quantitatively by a three-state model with the values of oxidation potential +0.3 and +1.2 V. KW - Polythiophene KW - In situ conductivity measurement KW - s24-Technique KW - Spectroelectrochemistry KW - Conducting polymers Y1 - 2011 U6 - https://doi.org/10.1007/s10008-011-1450-4 SN - 1433-0768 VL - 15 IS - 11 SP - 2377 EP - 2382 ER - TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Integrated electrochemical transistor as a fast recoverable gas sensor T2 - Analytica Chimica Acta N2 - A new design of conductometric chemical sensors based on conducting polymers as chemosensitive elements was suggested. The sensor includes six electrodes. Four inner electrodes coated by chemosensitive polymer are used for simultaneous two- and four-point resistance measurements thus providing information on the bulk polymer resistance and on the resistance of the polymer/electrode contacts. Two outer electrodes wired to inner electrodes by polymeric electrolyte are used for electrical control of redox state of the chemosensitive polymer. The outer electrodes are connected to potentiostat as reference and counter electrodes. It allows us to control redox state of the inner (working) electrodes. This new measurement configuration, resembling chemosensitive electrochemical transistors, provides an internal test of the sensor integrity and an electrically driven sensor regeneration. It was tested as a sensor for the detection of nitrogen dioxide. Polythiophene or polyaniline was used as receptors. Cyclic voltammograms of these polymers on the sensor surface measured in air atmosphere were very similar to that measured in aqueous electrolyte. A control of conductivity of these chemosensitive polymers by electrical potential applied vs. incorporated reference electrode was demonstrated. This effect was used for the regeneration of the chemosensitive material after exposure to nitrogen dioxide: in comparison to usual chemiresistors displaying an irreversible behavior in such test even in the time scale of hours, a completely reversible sensor regeneration within few minutes was observed. KW - Gas sensor KW - Conducting polyme KW - Electrochemical transistor KW - Six-point resistance Measurement KW - Sensor recovery Y1 - 2011 U6 - https://doi.org/10.1016/j.aca.2010.12.008 SN - 0003-2670 VL - 687 IS - 1 SP - 7 EP - 11 ER - TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Chemiresistors based on conducting polymers: A review on measurement techniques T2 - Analytica Chimica Acta N2 - This review covers the development of measurement configurations for chemiresistors based on conducting polymers. The simplest chemiresistors are based on application of a two-electrode technique. Artifacts caused by contact resistance can be overcome by application of a four-electrode technique. Simultaneous application of the two- and four-electrode measurement configurations provides an internal control of sensor integrity. An incorporation of two additional electrodes controlling the redox state of chemosensitive polymers and connecting to the measurement electrodes through liquid or (quasi)solid electrolyte results in a six-electrode technique; an electrically driven regeneration of such sensors allows one to perform fast and completely reversible measurements. KW - Chemiresistor KW - Chemotransistor KW - Conducting polymer KW - Chemosensor KW - Contact resistance KW - s24-Technique Y1 - 2011 U6 - https://doi.org/10.1016/j.aca.2010.11.030 SN - 0003-2670 VL - 687 IS - 2 SP - 105 EP - 113 ER - TY - GEN A1 - Lange, Ulrich A1 - Hirsch, Thomas A1 - Mirsky, Vladimir M. A1 - Wolfbeis, Otto S. T1 - Hydrogen sensor based on graphene - palladium nanocomposite T2 - Electrochimica Acta N2 - A composite material was prepared from graphene and palladium nanoparticles (PdNP) by layer-by-layer deposition on gold electrodes. The material was characterized by absorption spectroscopy, scanning electron microscopy, Raman spectroscopy and surface plasmon resonance. Cyclic voltammetry demonstrated the presence of electrocatalytic centers in the palladium decorated graphene. This material can serve as a sensor material for hydrogen at levels from 0.5 to 1% in synthetic air. Pure graphene is poorly sensitive to hydrogen, but incorporation of PdNPs increases its sensitivity by more than an order of magnitude. The effects of hydrogen, nitrogen dioxide and humidity were studied. Sensor regeneration is accelerated in humid air. The sensitivity of the nanocomposite depends on the number of bilayers of graphene–PdNPs. KW - Graphene KW - Palladium KW - Nanoparticle KW - Sensor KW - Layer-by-layer Y1 - 2011 U6 - https://doi.org/10.1016/j.electacta.2010.10.078 SN - 0013-4686 VL - 56 IS - 10 SP - 3707 EP - 3712 ER - TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Chemosensitive nanocomposite for conductometric detection of hydrazine and NADH T2 - Electrochimica Acta N2 - A new chemosensitive material based on palladium nanoparticles and PEDOT-PSS is described. The composite was characterized by transmission electron microscopy, cyclic voltammetry and in situ resistance measurements. The material was applied for conductometric detection of hydrazine and NADH. Upon exposure to these analytes PEDOT is reduced leading to an increase in its conductance. This process is catalyzed by palladium. A model for description of the potential dependence of polymer conductivity was suggested, tested and applied for the development of new calibration procedure of chemiresistors based on electroactive polymers. KW - Chemosensor KW - Chemiresistor KW - Nanoparticles KW - Palladium KW - PEDOT KW - Hydrazine KW - NADH Y1 - 2011 U6 - https://doi.org/10.1016/j.electacta.2010.08.092 SN - 0013-4686 VL - 56 IS - 10 SP - 3679 EP - 3684 ER - TY - GEN A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. T1 - Separated analysis of bulk and contact resistance of conducting polymers: comparison of simultaneous 2- and 4-point measurements with impedance measurements T2 - Journal of Electroanalytical Chemistry N2 - Simultaneous measurements of conductive polymer by two-and four-point techniques were used for evaluation of the contact resistance for the polymer/metal interface. An experimental validation of this approach was performed for polypyrrole electrochemically deposited on gold electrodes. The dependence of contact resistance on the electrode potential versus reference electrode was measured. The results were compared with the corresponding dependence obtained from impedance spectroscopy. Both techniques provide almost identical data while the new approach is easier, faster and independent on selection of equivalent circuits. KW - Conducting polymer KW - Polypyrrole KW - Contact resistance KW - Simultaneous two KW - Four-point measurements Y1 - 2008 U6 - https://doi.org/10.1016/j.jelechem.2008.06.013 SN - 1572-6657 VL - 622 IS - 2 SP - 246 EP - 251 ER - TY - GEN A1 - Lange, Ulrich A1 - Roznyatovskaya, Nataliya V. A1 - Mirsky, Vladimir M. T1 - Conducting polymers in chemical sensors and arrays (invited review) T2 - Analytica Chimica Acta N2 - The review covers main applications of conducting polymers in chemical sensors and biosensors. The first part is focused on intrinsic and induced receptor properties of conducting polymers, such as pH sensitivity, sensitivity to inorganic ions and organic molecules as well as sensitivity to gases. Induced receptor properties can be also formed by molecularly imprinted polymerization or by immobilization of biological receptors. Immobilization strategies are reviewed in the second part. The third part is focused on applications of conducting polymers as transducers and includes usual optical (fluorescence, SPR, etc.) and electrical (conductometric, amperometric, potentiometric, etc.) transducing techniques as well as organic chemosensitive semiconductor devices. An assembly of stable sensing structures requires strong binding of conducting polymers to solid supports. These aspects are discussed in the next part. Finally, an application of combinatorial synthesis and high-throughput analysis to the development and optimization of sensing materials is described. KW - Conducting polymers KW - Chemical sensors KW - Electroactive polymers KW - Gas sensors KW - Combinatorial techniques KW - Electropolymerization KW - Sensor array Y1 - 2008 U6 - https://doi.org/10.1016/j.aca.2008.02.068 SN - 0003-2670 VL - 614 IS - 1 SP - 1 EP - 26 ER - TY - CHAP A1 - Lange, Ulrich A1 - Roznyatovskaya, Nataliya V. A1 - Hao, Qingli A1 - Mirsky, Vladimir M. ED - Mirsky, Vladimir M. ED - Yatsimirsky, Anatoly K. T1 - Conducting polymers as artificial receptors in chemical sensors T2 - Artificial receptors for chemical sensors KW - artificial receptors polyaniline KW - chemosensors KW - conducting polymers KW - polyaniline KW - transducers Y1 - 2011 SN - 978-3-527-32357-9 U6 - https://doi.org/10.1002/9783527632480.ch12 SP - 363 EP - 392 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - Tsakova, Vessela T. A1 - Ivanov, Svetlozar D. A1 - Lange, Ulrich A1 - Stoyanova, Aneliya A1 - Lyutov, Vladimir V. A1 - Mirsky, Vladimir M. T1 - Electroanalytical applications of nanocomposites from conducting polymers and metallic nanoparticles prepared by layer-by-layer deposition T2 - Pure and Applied Chemistry N2 - Layer-by-layer (LbL) deposition is a convenient technique for the formation of ultra-thin nanocomposite layers containing metallic nanoparticles (NPs) and conducting polymers (CPs). The advantages of this approach for producing composite layers suitable for electroanalytical applications are discussed. Examples of electroanalytical applications of LbL-deposited composites are presented. Composite layers consisting of polyaniline (PANI) and Pd NPs are used for hydrazine oxidation. The PANI–Au NPs system is applied for dopamine (DA) and uric acid (UA) oxidation. KW - conducting polymers KW - dopamine KW - electrochemistry KW - hydrazine KW - layer-by-layer deposition KW - nanoparticles KW - polyaniline (PANI) KW - uric acid Y1 - 2010 U6 - https://doi.org/10.1351/PAC-CON-10-08-01 SN - 1365-3075 VL - 83 IS - 2 SP - 345 EP - 358 ER - TY - GEN A1 - Ivanov, Svetlozar D. A1 - Lange, Ulrich A1 - Tsakova, Vessela T. A1 - Mirsky, Vladimir M. T1 - Electrocatalytically active nanocomposite from palladium nanoparticles and polyaniline: Oxidation of hydrazine T2 - Sensors and Actuators B: Chemical N2 - The layer by layer (LbL) adsorption technique was used to deposit a new electrocatalytic material consisting of palladium nanoparticles (Pd NPs) and polyaniline (PANI). As far as PANI adsorption did not affect the reactivity of the Pd NPs attached in the former adsorption step, the LbL technique offered the way of increasing the reactive Pd surface within a three-dimensional nanocomposite structure. In situ conductance measurements have shown that depending on the concentration of the PANI solution, used for the LbL adsorption, composites with either PANI-like (dependent on potential and pH) or metal-like (non-dependent on potential and pH) conductive behaviour can be obtained. Metal-like Pd NPs–PANI nanocomposites were studied as electrocatalytic materials for hydrazine oxidation. A linear concentration dependence of the voltammetric peak currents was observed in the 40–800 μM hydrazine concentration range, the sensitivity increasing with the amount of adsorbed Pd NPs. Amperometric measurements showed linear response in the 10–300 μM range with sensitivity 0.5 μA/μmol cm−2 and a theoretical detection limit estimated to be 0.06 μM. KW - Conducting polymers KW - Pd-nanoparticles KW - LbL adsorption KW - Hydrazine Y1 - 2010 U6 - https://doi.org/10.1016/j.snb.2010.07.004 SN - 0925-4005 VL - 150 IS - 1 SP - 271 EP - 278 ER - TY - GEN A1 - Broncová, Gabriela A1 - Anikin, Sergey A1 - Lange, Ulrich A1 - Matějka, Pavel A1 - Krondak, Martin A1 - Král, Vladimír A1 - Mirsky, Vladimir M. T1 - Electrochemical and spectroscopic properties of poly-4,4′-dialkoxy-2,2′-bipyrroles T2 - Journal of Solid State Electrochemistry N2 - The structure and the electrochemical and spectral properties of two conductive electrochemically polymerized substituted bipyrroles 4,4′-methoxy-2,2′-bipyrrole and 4,4′-buthoxy-2,2′-bipyrrole were studied and compared. The polymers were characterized by cyclic voltammetry, FT-Raman spectroscopy, scanning electron microscopy, and in situ conductivity measurements at different pH and redox state. KW - Conducting polymer KW - Polydialkoxybipyrroles KW - Raman spectroscopy KW - Cyclic voltammetry KW - Conductivity Y1 - 2010 U6 - https://doi.org/10.1007/s10008-009-0911-5 SN - 1432-8488 SN - 1433-0768 VL - 14 IS - 6 SP - 1035 EP - 1044 ER - TY - GEN A1 - Lange, Ulrich A1 - Ivanov, Svetlozar D. A1 - Lyutov, Vladimir V. A1 - Tsakova, Vessela T. A1 - Mirsky, Vladimir M. T1 - Voltammetric and conductometric behaviour of self assembled multilayer nanocomposites of polyaniline and gold nanoparticles T2 - Journal of Solid State Electrochemistry N2 - Multilayer nanocomposites from polyaniline (PANI) and gold nanoparticles (AuNPs) were formed by layer-by-layer deposition. The formation of PANI–AuNPs multilayer structures was monitored by UV-vis absorption spectroscopy and cyclic voltammetry. Each deposited bilayer of PANI–AuNPs led to a monotonous and almost linear increase in both optical absorbance and the first current peak of PANI oxidation. The prepared multilayer nanocomposites were characterized by in situ conductivity measurements at different pH and potential and by transmission electron microscopy. Finally, chemosensitive properties of the new material based on the intrinsic affinity of gold nanoparticles were studied. Changes in the film resistance on exposure to vapors of mercury and sulfur-containing compounds were observed. KW - Polyaniline KW - Gold nanoparticles KW - Layer-by-layer deposition KW - Chemoresistor KW - In situ conductivity measurements KW - Nanocomposite Y1 - 2010 U6 - https://doi.org/10.1007/s10008-009-0922-2 SN - 1432-8488 SN - 1433-0768 VL - 14 IS - 7 SP - 1261 EP - 1268 ER - TY - CHAP A1 - Lange, Ulrich A1 - Mirsky, Vladimir M. ED - Hashmi, S. A. ED - Chandra, A. T1 - Potential and pH-dependencies of bulk and contact resistances of conducting polymers T2 - Electroactive polymers: Materials and devices, Vol. 3 Y1 - 2009 SP - 37 EP - 46 PB - Macmillan Publisher CY - New Delhi ER - TY - RPRT A1 - Hirschl, Bernd A1 - Reusswig, Fritz A1 - Lass, Wiebke A1 - Becker, Carlo W. A1 - Bölling, Lars A1 - Clausen, Wulf A1 - Haag, Leilah A1 - Hahmann, Henrike A1 - Heiduk, Philipp A1 - Hendzik, Manuel A1 - Henze, Anna A1 - Hollandt, Frank A1 - Hunsicker, Frank A1 - Lange, Christoph A1 - Meyer-Ohlendorf, Lutz A1 - Neumann, Anna A1 - Rupp, Johannes A1 - Schiefelbein, Sebastian A1 - Schwarz, Uwe A1 - Weyer, Gregor A1 - Wieler, Ulrich T1 - Klimaneutrales Berlin 2050 - Anhang zur Machbarkeitsstudie N2 - Die neue Landesregierung möchte Berlin beim Klimaschutz unter den Metropolen weltweit als Vorreiter etablieren. Die Erarbeitung der Machbarkeitsstudie „Klimaneutrales Berlin 2050“ im Auftrag der Senatsverwaltung für Stadtentwicklung und Umwelt soll auf diesem und für diesen Weg ein zentraler Baustein sein. Sie soll mögliche Entwicklungspfade für die Handlungsfelder Energiebereitstellung, Wohnen, Konsum, Wirtschaft und Mobilität aufzeigen sowie Maßnahmen und Leitprojekte für ein klimafreundliches Berlin vorschlagen. Koordiniert wird das Projekt vom Potsdamer Institut für Klimafolgenforschung (PIK). Der Anhang soll vor allem einen Kurzüberblick über die zur Erreichung des Klimaneutralitäts-Ziel vorgeschlagenen Maßnahmen geben. KW - klimaneutrales Berlin Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:101:1-2014081410066 UR - https://www.ioew.de/fileadmin/user_upload/BILDER_und_Downloaddateien/Publikationen/2014/Hirschl_Bernd_Machbarkeitsstudie_Klimaneutrales_Berlin_2050_Anhang.pdf PB - Senatsverwaltung für Stadtentwicklung und Umwelt CY - Berlin ER - TY - PAT A1 - Mirsky, Vladimir M. A1 - Lange, Ulrich T1 - Multielectrode chemoresistor Y1 - 2010 ER -