General characteristics of the copper-based mercury film electrode

The optimum conditions for the preparation, storage, conditioning and renewal of copper-based mercury film electrodes (CBMFEs) are given. The voltammetric results obtained at these electrodes are compared with the predictions of the theory of cyclic and stripping voltammetry at the mercury film electrode, as well as with the results obtained at the silver-based and the platinum-based mercury film electrodes. The advantage of a CBMFE is prolonged life-time, whereas the disadvantages ar the decreased range of usable positive potentials and the possibility of interfering reactions of the electrodeposited metals with the copper substrate or copper dissolved in the mercury phase. The presence of copper has no essential influence on the behaviour of lead and thallium; it affects the behaviour of zinc markedly and that of cadmium and indium slightly. The conditions allowing the minimization of the harmful action of copper on the behaviour of cadmium and indium have been found.