Demonstration of an Iron Oxide Mediated Solar Decoupled Electrolysis Cycle
Arts and Sciences
A solar decoupled electrolysis cycle with iron oxide mediators first proposed eleven years ago is demonstrated here. The James Markiewicz Solar Energy Research Facility (SERF) at Valparaiso University uses concentrated sunlight to reduce hematite at 1500 ℃, evolving oxygen and producing magnetite. Magnetite can then be dissolved in water at pH 5 using hydroxyethylidene diphosphonic acid (HEDP). Aqueous Fe2+ serves as the anode for the reduction of water to hydrogen, as demonstrated by a visual H2 detection assay. Finally, alkaline solutions of Fe3+ + HEDP upon concentration produce a precipitate characterized as goethite α-FeOOH by Raman spectroscopy, completing the cycle.
Hill, Sarah and Smith, Paul, "Demonstration of an Iron Oxide Mediated Solar Decoupled Electrolysis Cycle" (2023). Summer Interdisciplinary Research Symposium. 139.