Mercury electrode: advantages

The majority of work on the electrified interface has been carried out using a mercury electrode, which has the advantage that it has a well-defined and reproducible surface and a highly polarisable interface when immersed in a solution. In the case of solid metals the concepts outlined are equally applicable, but modifications are necessary to allow for the following ... 

One of the outstanding advantages of the mercury cathode is that the optimum control potential for a given separation is easily determinable from polarograms recorded with the dropping mercury electrode. This potential... 

By far, most of electrochemical kinetic data that can be subjected to detailed analysis has been obtained at the mercury-aqueous electrolyte interface or at mercury electrodes in other solvents (1-4.16L The main advantages of mercury over other... 

What are two advantages of the dropping mercury electrode over a stationary electrode ... 

The first hydrodynamic electrode to be invented was the dropping mercury electrode [1]. It has a cyclic operation and can thus be considered only as quasi-steady-state its hydrodynamic character derives from drop growth. The principal advantage of a dropping electrode is that a fresh electrode surface is constantly exposed to the solution however, there are few electrode materials available and mathematical solution of the mass transport to the drop surface is complicated by the fact that the surface is expanding. 

Tire dropping mercury electrode has been studied extensively. Its greatest advantage is that it represents a highly reproducible, clean... 

In the first part of this century, electrochemical research was mainly devoted to the mercury electrode in an aqueous electrolyte solution. A mercury electrode has a number of advantageous properties for electrochemical research its surface can be kept clean, it has a large overpotential for hydrogen evolution and both the interfacial tension and capacitance can be measured. In his famous review [1], D. C. Grahame made the firm statement that Nearly everything one desires to know about the electrical double layer is ascertainable with mercury surfaces if it is ascertainable at all. At that time, electrochemistry was a self-contained field with a natural basis in thermodynamics and chemical kinetics. Meanwhile, the development of quantum mechanics led to considerable progress in solid-state physics and, later, to the understanding of electrostatic and electrodynamic phenomena at metal and semiconductor interfaces. 

Experimental investigations with mercury electrodes were very successful in the first half of this century [1], Mercury has the advantage of offering a very dean surface. Moreover, with a hanging mercury drop electrode, measurement of not only the interfacial capacitance, but also the interfacial surface tension as a function of surface charge density is possible. A combination of careful experiments and subtle thermodynamic theory led to a detailed empirical picture of the mercury/... 

The dropping mercury electrode has two main advantages when used... 

Polarography is the term used for voltammetry with the dropping mercury electrode (DME). The technique has been discussed extensively in several textbooks and reviews [1-, 237-242] to which the reader is referred for details concerning both theoretical problems and practical applications. The electrode (Fig. 31) was developed early in the century by Heyrovsky and was the dominating tool in electroanalytical chemistry for several decades. Because of the low oxidation potential of mercury (0.3-0.4 V versus SCE), the DME has been used almost exclusively for the study of reduction processes. Compared with mercury film electrodes, the DME offers the advantage that the electrode surface is continuously renewed. This property reduces undesirable surface effects caused by adsorption. 

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