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Time-resolved potentiometry on liquid-liquid interface
Mansfeldová, Věra
MSc. Věra Mansfeldová Dissertation thesis: Time-resolved potentiometry on liquid-liquid interface Abstract The aim of this work is to explore the method of temporal resolution in potentiometry as a new prospective electrochemical analytical technique. In connection with interface of two immiscible electrolyte solutions (ITIES) it may find utilization in analytical chemistry. This technique up to my knowledge has not been published yet. Potential response of analyte on liquid/liquid interface includes both distribution processes, their temporal resolution and redox processes, which specificity can modified by changing the composition of individual phases. Unlike "classic" potentiometric techniques, limited just to potential determination, this method, which I have given the working name "time resolved potentiometry at liquid-liquid interface" utilizes time development of potential response, which was found to be an analyte-specific function. The time resolved potentiometry presented in this work includes time course of potential response to analytical parameters specific for particular analyte. It brings series of data characterizing the analyte in given environment in a similar manner as spectra and may allow creating analyte-specific data package - fingerprint. Combination with ITIES allows, unlike...
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ELECTROCHEMICAL STUDY OF CuSCN INORGANIC HOLE-TRANSPORT MATERIAL FOR SOLAR CELLS PREPARED BY ELECTRODEPOSITION FROM AQUEOUS SOLUTION
Vlčková Živcová, Zuzana ; Mansfeldová, Věra ; Bouša, Milan ; Kavan, Ladislav
A comparative study is reported for electrodeposited copper(I) thiocyanate layers (ca. 500 nm) on two types of conductive/semiconductive substrates: i) carbon (boron-doped diamond_BDD, glass-like carbon_GC), and ii) carbon-free F-doped SnO2 conducting glass (FTO). SEM and Raman evidence that electrodeposition from aqueous solution results in homogenous CuSCN layers with dominant thiocyanate ion bounded to copper through its S-end (Cu−SCN bonding), as in spin-coated CuSCN layers. Electrochemical impedance spectroscopy (EIS) confirms the p-type semiconductivity of layers with a flatband potential from 0.1 to 0.18 V vs. Ag/AgCl depending on the substrate type, and the acceptor concentration (NA) of 5 x 1020cm-3 in all cases. The flatband potentials determined from Mott-Schottky plots (EIS) are in good agreement with the Kelvin probe measurements. The blocking quality of CuSCN layers was tested using Ru(NH3)63+/2+ redox probe. CuSCN deposited on BDD substrate exhibits better blocking properties compared to CuSCN deposited on FTO.
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Time-resolved potentiometry on liquid-liquid interface
Mansfeldová, Věra ; Nesměrák, Karel (advisor) ; Opekar, František (referee) ; Gál, Miroslav (referee)
Věra Mansfeldová: Time-resolved potentiometry on liquid-liquid interface (Dissertation thesis) Abstract The aim of this work is to explore the method of temporal resolution in potentiometry as a new prospective electrochemical analytical technique. In connection with interface of two immiscible electrolyte solutions (ITIES) it may find utilization in analytical chemistry. This technique up to my knowledge has not been published yet. Potential response of analyte on liquid/liquid interface includes both distribution processes, their temporal resolution and redox processes, which specificity can modified by changing the composition of individual phases. Unlike "classic" potentiometric techniques, limited just to potential determination, this method, which I have given the working name "time resolved potentiometry at liquid-liquid interface" utilizes time development of potential response, which was found to be an analyte-specific function. The time resolved potentiometry presented in this work includes time course of potential response to analytical parameters specific for particular analyte. It brings series of data characterizing the analyte in given environment in a similar manner as spectra and may allow creating analyte-specific data package - fingerprint. Combination with ITIES allows, unlike...
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Time-resolved potentiometry on liquid-liquid interface
Mansfeldová, Věra
MSc. Věra Mansfeldová Dissertation thesis: Time-resolved potentiometry on liquid-liquid interface Abstract The aim of this work is to explore the method of temporal resolution in potentiometry as a new prospective electrochemical analytical technique. In connection with interface of two immiscible electrolyte solutions (ITIES) it may find utilization in analytical chemistry. This technique up to my knowledge has not been published yet. Potential response of analyte on liquid/liquid interface includes both distribution processes, their temporal resolution and redox processes, which specificity can modified by changing the composition of individual phases. Unlike "classic" potentiometric techniques, limited just to potential determination, this method, which I have given the working name "time resolved potentiometry at liquid-liquid interface" utilizes time development of potential response, which was found to be an analyte-specific function. The time resolved potentiometry presented in this work includes time course of potential response to analytical parameters specific for particular analyte. It brings series of data characterizing the analyte in given environment in a similar manner as spectra and may allow creating analyte-specific data package - fingerprint. Combination with ITIES allows, unlike...
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Electroanalysis with phthalocyanine modified HOPG electrodes
Mansfeldová, Věra ; Janda, Pavel
In this papers we presented modification of highly oriented pyrolitic graphite (HOPG) by two different phthalocyanine (Pc) derivatives and two different deposition techniques. We have investigated electrode modified by fullerene-derived phthalocyanine and cobalt tetraneopentoxyphthalocyanine (CoTNPc) to consider how different modification procedure-electrodeposition and drop evaporation and composition of phthalocyanine influences detection of model compound, L-cysteine.
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Electrochemical sensor: Mediator Deposition by drop evaporation
Mansfeldová, Věra ; Janda, Pavel ; Tarábková, Hana
Among many different kinds of electrode surface modification procedures, the surface coating by vaporized mediator solution is still used as a simple and effective method for preparation of sensing electrode. Surface of glassy carbon (GC) is often used as a supporting collector, but it requires polishing, rinsing and sonication prior to mediator deposition. In this paper, we present common methods of modification of highly oriented pyrolytic graphite (HOPG) and GC surface, respectively, from the point of surface nanomorphology investigated by atomic force microscopy.
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Electrode coating by chemical mediator: The atomic force microscopy study of surface nanomorphology
Mansfeldová, Věra ; Janda, Pavel ; Tarábková, Hana
Among many different kinds of electrode surface modification procedures, the surface coating by vaporized mediator solution is still as a simple and effective method for preparation of sensing electrode. Surface of glassy carbon (GC) is often used as a supporting collector, but it requires polishing, rinsing and sonication prior to mediator deposition. In this paper, we present common methods of modification of highly oriented pyrolytic graphite (HOPG) and GC surface, respectively, from the point of surface nanomorphology investigated by atomic force microscopy (AFM).
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