SUMMARY

The development of a clean, sustainable energy infrastructure is a significant technological challenge of the future, particularly fuel generation for the transportation sector. One approach is to store energy from solar radiation chemically by splitting water to produce hydrogen, a dispatchable fuel. This can be achieved many ways, but one of the most promising methods is solar driven two-step thermochemical redox cycles. In these cycles, an oxygen storage material (OSM) is used to break the reaction into steps where the sum of the reaction steps results in water splitting These cycles require lower temperatures than direct water thermolysis and have relatively high theoretical efficiency. However, the high predicted efficiencies of these cycles have yet to be demonstrated. By understanding the strong coupling between OSM thermodynamic properties and reactor design, a model was constructed to incorporate vacuum pump losses as well as the losses associated with preheating unreacted reaction products. The model was used to qantify the efficiency improvements that can be achieved by lowering the magnitude of the OSM reduction enthalpy. The results of this model were used to guide a thermogravimetric screening of a Lanthanum, Aluminum based perovskites as OSM’s for thermochemical cycles.