Search results for "Chemically modified"
showing 6 items of 6 documents
Electrodes with Immobilized Particles and Droplets: Three-Phase Electrodes
2014
It is a common feature of electrodes with immobilized particles and droplets that three phases are in close contact with each other, i.e., each phase having an interface with the two other phases. This situation exists also in most of the so-called surface-modified or film electrodes, many battery and fuel cell electrodes, electrodes of the second kind, etc. In fact, the majority of surface-modified electrodes consist of arrays of particles that partially cover the electrode surface. It would be far beyond the scope of this book to include all chemical and electrochemical techniques to deposit films on electrodes. Here we shall deal only with electrodes where the particles or droplets have …
eta1-Allypalladium complexes with tridentate PNP’ ligand for the assembly of modified Screen Printed Electrodes: an electrochemical study.
2015
Specific Pd-based organometallic complex, in particular the [Pd(η1-CH2–CH=CH2)(P–N–P’)]BF4 was used for the assembly of chemically modified Screen Printed Electrodes (SPEs) and their electrochemical reactivity was also investigated. For this purpose potassium ferricyanide, hexaammineruthenium(III) chloride, sodium hexachloroiridate-(III) hydrate, ascorbic acid (AA), uric acid (UA), acetaminophen (Ac), guanine (G) and adenine (A) were used to study the electron-transfer processes, which occurred at modified SPEs, fabricated by using the [Pd(η1-CH2–CH=CH2)(P–N–P’)]BF4, applying the drop casting procedure. Interesting results were obtained in the case of the guanine (G) quantitative detection,…
Electrochemistry of Carbon Dioxide on Carbon Electrodes.
2016
Carbon electrodes have the advantages of being chemically inert at negative potential ranges in all media and high offset potentials for hydrogen evolution in comparison to metal electrodes, and therefore are the most suitable electrodes for electrochemistry and electrochemical conversion of CO2 into valuable chemicals. Herein we summarize on carbon electrodes the voltammetry, electrochemical and electrocatalytic CO2 reduction, as well as electron synthesis using CO2 and carbon electrodes. The electrocatalytic CO2 reduction using carbocatalyts and the future activities about electrochemical CO2 conversion are highlighted.
Nanocomposites based on esterified colophony and halloysite clay nanotubes as consolidants for waterlogged archaeological woods
2017
We have designed an innovative protocol for the consolidation of waterlogged archaeological woods by using acetone mixtures of halloysite clay nanotubes and a chemically modified colophony (Rosin). Firstly, we have investigated the thermal properties of HNTs/Rosin nanocomposites, which have been prepared by means of the casting method from acetone. The HNTs content have been systematically changed in order to study the influence of the inorganic filler on the thermal stability and glass transition process of Rosin. We have observed that the thermal properties of the hybrids are affected by the specific HNTs/Rosin interactions. Then, acetone dispersions of HNTs/Rosin composites at variable f…
Novel Ni(II) Mixed Ligand Complex Modified Electrode: Catalytic Effect on Anodic Oxidation of Phenol
2004
Cyclic voltammetry, using graphite paste electrode (GPE) and chemically modified GPE with Ni(II) mixed ligand complex (MGPE), is described for sensing and detoxification of phenol. A novel mixed ligand complex of nickel with 1,4,8,11-tetraaza cyclotetradecane (cyclam) and thiocyanate in the molar ratio of 1 : 2 : 5 is synthesized and characterized by spectroscopic and electrochemical studies. The Ni(II)-cyclam-thiocyanate complex behaves as a fast electron-transfer mediator, as nickel ions exist in higher oxidation state of Ni(III) on applying a potential of 1.25 V (vs. Ag/AgCl), which catalyses the oxidation of the target species. The mixed ligand complex, when incorporated in the graphite…
Atomic force microscopy study of conducting polymer films near electrode's edge or grown on microband electrode
2013
Abstract Polypyrrole (PPy) films of different thicknesses (within the range from 200 nm to 2.5 μm) were electrodeposited on two types of inhomogeneous substrates, single band and double-band Pt electrodes. Topographic images of the polymer layers were obtained by means of ex situ large-scale AFM technique to demonstrate how the propagation rates of the film growth above the electrode (in the normal direction to the electrode surface) and along the insulating surface surrounding the single- or double-band electrodes (in the horizontal direction) change with the deposition charge. It is proved that variations in the film thickness over the double band electrodes and progressive changes of the…