An Iron Oxide Mediated Solar Decoupled Electrolysis Cycle

Authors

Sarah Hill, Valparaiso UniversityFollow
Paul F. Smith, Valparaiso UniversityFollow

Level of Education of Students Involved

Undergraduate

Faculty Sponsor

Paul Smith

College

College of Arts & Sciences (CAS)

Discipline(s)

Chemistry

ORCID Identifier(s)

0000-0001-5223-0690

Presentation Type

Oral Presentation

Symposium Date

Spring 4-24-2025

Abstract

We present a proof of concept demonstration of solar thermochemical energy storage. 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.

Recommended Citation

Hill, Sarah and Smith, Paul F., "An Iron Oxide Mediated Solar Decoupled Electrolysis Cycle" (2025). Symposium on Undergraduate Research and Creative Expression (SOURCE). 1379.
https://scholar.valpo.edu/cus/1379