Author
Ewa Rozniecka
Other affiliations: University of Michigan, Warsaw University of Technology, University of Warsaw
Bio: Ewa Rozniecka is an academic researcher from Polish Academy of Sciences. The author has contributed to research in topics: Cyclic voltammetry & Redox. The author has an hindex of 12, co-authored 23 publications receiving 421 citations. Previous affiliations of Ewa Rozniecka include University of Michigan & Warsaw University of Technology.
Topics: Cyclic voltammetry, Redox, Electrode, Aqueous solution, Voltammetry
Papers
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TL;DR: In this article, a silicate carbon composite material was modified with redox probe (t-butylferrocene) solution in ionic liquid (1-butyl-3methylimidazolium hexafluorophosphate or 1-decyl- 3methyloridazolate bis(trifluoromethylsulfonyl)imide).
85 citations
TL;DR: In this paper, a 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate) modified electrode was obtained by sol-gel processing of methyltrimethoxysilane based sol with dissolved ABTS 2− together with dispersed graphite particles.
50 citations
TL;DR: Under optimized conditions, optical selectivity coefficients toward chloride over a wide range of other anions are measured to be < 10(-3), which is adequate for reversible and accurate sensing of chloride levels in diluted serum samples.
Abstract: A novel transduction chemistry for preparing optical anion-selective polymeric films that respond reversibly and selectively to chloride ion activity is demonstrated. The chloride sensors are prepared by casting thin (5-10 microm) plasticized PVC films containing indium(III) octaethylporphyrin hydroxide, along with optimized levels of a lipophilic tetraphenylborate salt, onto glass slides. When bathed in low-pH buffered solutions void of chloride, the porphyrin species spontaneously forms a hydroxide ion-bridged dimer, with the added lipophilic borate species serving as the counteranion for this complex. The maximum for the Soret absorption band of this dimeric species is shifted to 390 nm, from 410 nm for the initial monomeric porphyrin. Increases in chloride ion levels in the bathing solution results in chloride extraction and ligation to the In(III) center, and concomitant breaking of the dimer into monomeric porphyrin species, yielding a decrease in absorbance at 390 nm and an increase in optical signal at 410 nm. Under optimized conditions, optical selectivity coefficients toward chloride over a wide range of other anions (NO3-, ClO4-, SCN-, SO4(2-), F-, Br-, H2PO4-) are measured to be < 10(-3). Of all anions tested, only salicylate yields a slightly greater response than chloride. This selectivity is shown to be adequate for reversible and accurate sensing of chloride levels in diluted serum samples.
46 citations
TL;DR: In this paper, a thin film of carbon nanofibers embedded into a hydrophobic sol-gel material and deposited onto tin-doped indium oxide substrate electrodes is employed as a support for liquid|liquid redox systems.
34 citations
TL;DR: Ion transfer across the boundary formed at an ionic liquid drop deposited on an electrode immersed in aqueous solution, generated by electrochemical redox reaction at the electrode-ionic liquid interface, is studied to obtain information about the ability of anions to be transferred into a room temperature ionic Liquid.
28 citations
Cited by
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TL;DR: This review focuses on the application of ILs in electroanalytical sensors, which have been found to have good biocompatibility with enzymes, proteins and even living cells.
647 citations
TL;DR: This work discusses the different methodologies of enzyme immobilization that have been reported for laccases, such as adsorption, entrapment, encapsulation, covalent binding and self-immobilization.
530 citations
TL;DR: The effect of water content on room-temperature ionic liquids (RTILs) was studied by Karl Fischer titration and cyclic voltammetry in the following RTILs: tris(P-hexyl)tetradecylphosphonium trifluorotris(pentafluoroethyl)phosphate [P14,6,6 6,6],NTf2], N-butyl-N-methyl-pyrrolidinium bis(triffluoromethylsulfonyl)im
Abstract: The effect of water content on room-temperature ionic liquids (RTILs) was studied by Karl Fischer titration and cyclic voltammetry in the following ionic liquids: tris(P-hexyl)tetradecylphosphonium trifluorotris(pentafluoroethyl)phosphate [P14,6,6,6][NTf2], N-butyl-N-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide [C4mpyrr][NTf2], 1-hexyl-3-methylimidazolium tris(perfluoroethyl)trifluorophosphate [C6mim][FAP], 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C4mim][NTf2], 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C4dmim][NTf2], N-hexyltriethylammonium bis(trifluoromethylsolfonyl)imide [N6,2,2,2][NTf2], 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6], 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [C2mim][NTf2], 1-butyl-3-methylimidazolium tetrafluoroborate [C4mim][BF4], 1-hexyl-3-methylimidazolium iodide [C4mim][I], 1-butyl-3-methylimidazolium trifluoromethylsulfonate [C4mim][OTf], and 1-hexyl-3-methylimidazolium chloride [C6mim][Cl]. I...
509 citations
TL;DR: The thermochemistry of oxygen reduction and the factors influencing ORR efficiency are described to contextualize the discussion of catalytic studies that follows, and reports of ORR catalysis are presented in terms of their mechanism.
Abstract: The oxygen reduction reaction (ORR) is a key component of biological processes and energy technologies This Review provides a comprehensive report of soluble molecular catalysts and electrocatalysts for the ORR The precise synthetic control and relative ease of mechanistic study for homogeneous molecular catalysts, as compared to heterogeneous materials or surface-adsorbed species, enables a detailed understanding of the individual steps of ORR catalysis Thus, the Review places particular emphasis on ORR mechanism and thermodynamics First, the thermochemistry of oxygen reduction and the factors influencing ORR efficiency are described to contextualize the discussion of catalytic studies that follows Reports of ORR catalysis are presented in terms of their mechanism, with separate sections for catalysis proceeding via initial outer- and inner-sphere electron transfer to O2 The rates and selectivities (for production of H2O2 vs H2O) of these catalysts are provided, along with suggested methods for acc
384 citations
TL;DR: This review provides a comprehensive summary of the experimental parameters used in all SECM publications since 1989, irrespective of the application, and can be used to rapidly assess experimental possibilities and make an informed decision about experimental design.
Abstract: Scanning electrochemical microscopy (SECM) is an electroanalytical scanning probe technique capable of imaging substrate topography and local reactivity with high resolution. Since its inception in 1989, it has expanded into a wide variety of research areas including biology, corrosion, energy, kinetics, instrumental development, and surface modification. In the past 25 years, over 1800 peer-reviewed publications have focused on SECM, including several topical reviews. However, these reviews often omit key details, forcing readers to search the literature. In this review, we provide a comprehensive summary of the experimental parameters (e.g., solvents, probes, and mediators) used in all SECM publications since 1989, irrespective of the application. It can be used to rapidly assess experimental possibilities and make an informed decision about experimental design. In other words, it is a practical guide to SECM.
304 citations