09074 IUPAC Gold Book - electrode surface area 10.1351/goldbook.09074 09074 current 1 Area of electrode–solution interface. The geometric area, \(A_{\rm{geom}}\), is the interfacial area, determined on the assumption that the interface is truly flat (two-dimensional) and calculated using the geometric data of the involved surfaces. The real (true) area, \(A_{\rm{real}}\), takes into account non-idealities of the interface (roughness, porosity, etc.) and can be measured by a variety of electrochemical methods. The electroactive area is the area calculated from experiments with model electroactive species and may be different from the real surface area in cases where not all of the surface is electrochemically active or accessible. PAC, 2020, 92, 641. 'Terminology of Electrochemical Methods of Analysis (IUPAC Recommendations 2019)' on page 653 (https://doi.org/10.1515/pac-2018-0109) https://goldbook.iupac.org/terms/view/09074/html https://goldbook.iupac.org/terms/view/09074/json https://goldbook.iupac.org/terms/view/09074/plain Citation: 'electrode surface area' 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.09074 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. 2026-05-11T19:59:58+00:00