Volume 16, Issue 4, 1998
17th October, 2022
by MA.N.D.A. Lemos, F. Lemos, N. Papadopoulos, A.J.L. Pombeiro
175-180
DOI: doi:10.4152/pea.199804175
In this paper we discuss the advantages of using interactive simulation programmes for electrochemical dynamical experiments to help both researchers and students in understanding the phenomena underlying these experiments, as well as in obtaining meaningful chemical and electrochemical parameters associated with the redox transformation mechanisms. A PC computer programme developed for this purpose, and which is available to anyone interested, is also presented and applied to the demonstration of virtual cyclic voltammetry.
Electro-Oxidation of Methanol on Porous Unsupported Pt-Ru Alloy Electrodes in Strong Alkali and Strong Acid
Read Abstract
by J. Prabhuram, R. Manoharan
181-193
DOI: doi: 10.4152/pea.199804181
Porous unsupported Pt-Ru single phase alloy electrodes with different compositions viz., 9:1, 7:3 and 5:5 are prepared by NaBFL reduction method at room temperature. The reactivity of these alloy electrodes towards the methanol oxidation reaction (MOR) is systematically investigated in different electrolytes of high and low pH with various quantities of methanol at room temperature by using cyclic voltammetric (CV) and steady-state galvanostatic polarisation techniques. Various electrochemical processes occurring in different potential regions are discussed. The highest activity of the MOR is obtained for a 7:3 electrode in 2.5 M H2S04 / 2.5 M CH3OH and in 6 M KOH / 6 M CH3OH mixtures, respectively. It is concluded that by choosing the proper ratio of OH ions and CH3OH in solution, it is possible to remove completely the intermediate organic species and/or poisonous species that retard the MOR.
Synthesis and Cyclic Voltammetric Studies of Some Complexes of Cobalt(II), Nickel(II), Manganese(II) and Copper(II) with 2,2'-Bi-4,5-dihydrothiazine (btz) and 2,2'-Bi-2-thiazoline (bt)
Read Abstract
by M. Fernanda Cabral, João O. Cabral, Pedro Oliveira
195-205
DOI: doi:10.4152/pea.199804195
Four complexes of 2,2'-bi-4,5-dihydrothiazine (btz) with Co(II), Ni(II), Mn(II) and Cu(II), and two complexes of 2,2'-bi-thiazoline (bt) with Co(II) were synthesized and characterized, three of them, the Mn(II) complex and the two bt complexes, for the first time. These six complexes were studied using cyclic voltammetry in acetonitrile solution.All displayed reversible or quasi-reversible behaviour, and two waves were observed in the case of [Co(btz)3] [C104]2- All the results are described and discussed.
Study of Oxide Films Formed on Iridium Implanted Ti-6A1-4V Alloy
Read Abstract
by T. M. Silva, M. G. S. Ferreira, M. da Cunha Belo
207-219
DOI: doi:10.4152/pea.199804207
The oxide films formed by potential cycling on commercial Ti6A14V alloy, that has been surface implanted with iridium, are studied by capacitance measurements and Auger analysis. It is observed that these films become enriched in iridium when etched in sulphuric acid solution prior to their formation, simultaneously with a change in the type of semiconductivity (n-type to p-type).
The Use of Basic Concepts of Electrochemistry in Industry
Read Abstract
by Victor M .M. Lobo
221-226
DOI: doi:10.4152/pea.199804221
An outline of a document with a basic vocabulary used in electrochemical industries is indicated following an historical development with references to sources where it would be properly explained. The objective would be to avoid having to include "definitions" on elementary concepts in CEN and ISO standards. The inadequacy of those definitions in standards is indicated and the present approach is justified.
by M .F. C. Guedes da Silva
227-229
DOI: doi:10.4152/pea.199804227
