A NOVEL MODEL OF THE HANGING MERCURY DROP ELECTRODE

A novel version of a home-made hanging mercury drop electrode (HME) pr epared in our laboratory is presented. Its main technical features are described, as well as the advantages it offers over the commercial on es. With this version the area of the electrode surface can be measure d with great accuracy, and the reproducibility of the area from one me rcury drop to another is better than 1 x 10(-3) cm(2), corresponding t o less than 1% of the total amount of the surface area of an average m ercury drop. The constancy of the area, for time periods of up to 90 m in, and the reproducibility from one drop to another make this version of HME suitable for use in the analytical field in the study of adsor ption or electron transfer phenomena when it is necessary to know the exact electrode surface area in order to determine surface density cha rge or differential capacitance values. (C) 1997 Elsevier Science S.A.