09102 IUPAC Gold Book - mercury electrode 10.1351/goldbook.09102 09102 current mentioned: mercury film electrode (MFE), thin mercury film electrode (TMFE) 1 Liquid metal electrode used in polarography. Liquid mercury is an ideal electrode material for negative potentials because of its high overpotential for hydrogen evolution (electrochemical reduction of hydroxonium cations from solution). However, mercury is readily oxidized, particularly in the presence of anions that form complexes or that precipitate with \(\ce{Hg(I)}\) or \(\ce{Hg(II)}\) ions, and thus it is not suitable for use at positive potentials. The use of liquid mercury has largely been discontinued because of concerns about the toxicity of the element and its compounds. A mercury film electrode (MFE) or thin mercury film electrode (TMFE) is formed by coating a conducting substrate, usually glassy carbon, with a layer of mercury (thin film, amalgam, or array of microdrops), often by electrodeposition from a solution containing \(\ce{Hg(II)}\). The electrode area is normally in the range of \(\pu{0.1 to\, 0.5 cm2}\) and mercury film thickness typically ranges from \(\pu{10 to 1000 nm}\), producing a film of large surface area-to-volume ratio that results in a high analyte pre-concentration during the deposition step of anodic stripping voltammetry. Compared to an HMDE, the MFE provides high sensitivity and resolution; however, it is somewhat less reproducible and more prone to interferences from intermetallic formation and surface-active substances. HMDE https://goldbook.iupac.org//terms/view/09103 anodic stripping voltammetry https://goldbook.iupac.org//terms/view/09152 electrode https://goldbook.iupac.org//terms/view/09060 polarography https://goldbook.iupac.org//terms/view/09135 PAC, 2020, 92, 641. 'Terminology of Electrochemical Methods of Analysis (IUPAC Recommendations 2019)' on page 660 (https://doi.org/10.1515/pac-2018-0109) https://goldbook.iupac.org/terms/view/09102/html https://goldbook.iupac.org/terms/view/09102/json https://goldbook.iupac.org/terms/view/09102/plain Citation: 'mercury electrode' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.09102 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-04-18T11:06:21+00:00