Search results for "Potentiometric sensor"
showing 3 items of 3 documents
Electrochemical behaviour of poly(neutral red) on an ITO electrode
1998
Abstract The formation of a radical cation, by electrochemical oxidation of the neutral red dye in acidic aqueous solution, is controlled by diffusion towards the electrode surface. This is the initiation step of the electrogeneration, potentiostatic or potentiodynamic, of poly(neutral red) films on an indium–tin oxide (ITO) electrode. The polymeric film is a redox semi-conductor, and shows a microporous membrane-like character. Its electrochemical behaviour depends on the generation process. The hydrogen ions play a double role: first as reactants at electrochemical and acid–base equilibrium, second as counterions of the electrons. The global process of the electron-hopping is limited by t…
Solid Contact Potentiometric Sensors Based on a New Class of Ionic Liquids on Thiacalixarene Platform
2018
New solid-contact potentiometric sensors have been developed for hydrogen phosphate recognition on the basis of ionic liquids containing tetrasubstituted derivatives of thiacalix[4]arene in cone and 1,3-alternate conformations with trimethyl- and triethylammonium fragments at the lower rim substituents. The recognition of selected anions including carbonate, hydrogen phosphate, perchlorate, oxalate, picrate, and EDTA was conducted using electrochemical impedance spectroscopy with ferricyanide redox probe. For the potentiometric sensor assembling, the ionic liquids were stabilized by multiwalled carbon nanotubes and carbon black deposited on the glassy carbon electrode. The influence of supp…
A logarithmic multi-parameter model using gas sensor main and cross sensitivities to estimate gas concentrations in a gas mixture for SnO2 gas sensors
2007
Abstract In a metal-oxide semiconductor gas sensor, the sensitivity of the metal-oxide resistance to concentrations of reducing gases in the surrounding atmosphere is known to be related to adsorption and desorption of gas on the redox reactions between the gas and oxygen. Changes in the electric conductance due to these reactions were measured for tin dioxide semiconductor gas sensors. In this study, we propose a model of gas sensor responding behaviour using a relationship between sensor conductance and gas concentrations in a mixture. A least-squares method fit of measured data was applied to determining the values of coefficients. The proposed method uses main and cross sensitivities th…