(515n) Experimental Comparison of Metal Oxide Materials for Solar Thermal Water Splitting

Renewable H₂ is produced from water using concentrated sunlight to drive the endothermic water splitting reaction via a solar thermochemical hydrogen (STCH) redox cycle. These redox cycles use metal oxide intermediates (fluorites, perovskites, spinels) at high temperatures. Although much effort has been directed towards computational analysis to discover new materials, less effort has been given to directly compare these materials experimentally to date. Here, we compare different solar thermal water splitting (STWS) materials and evaluate their performance under various operating conditions for H₂ production capacity, kinetics, water consumed to hydrogen produced (H₂O:H₂) ratio, and stability (robustness) using a stagnation flow reactor. A direct comparison of materials performance provides researchers with a path forward regarding process efficiency and cost.