Redox Performance of Ceria-Vanadia Mixed-Phase Reticulated Porous Ceramics for Solar Thermochemical Syngas Production

Solar energy-driven thermochemical redox cycles are a promising method of synthesis gas production. Oxygen exchange materials are key chemical components directly affecting overall solar-to-fuel efficiency. In this work, we investigate the development and performance of ceria-vanadia mixed-phase reticulated porous ceramics used in methane partial oxidation coupled to carbon dioxide splitting reactions for solar production of synthesis gas. The mechanical robustness and redox capability with high oxygen exchange capacity are demonstrated over 20 consecutive thermochemical cycles. The cycle-average hydrogen and carbon monoxide production rates during the methane partial oxidation are up to 11.1 and 5.3 mL min-1 g-1, respectively. For the carbon dioxide splitting reaction, the average CO production rate is up to 4.5 mL min-1 g-1. Ceria-vanadia mixed-phase reticulated porous ceramics are shown to have a high degree of chemical and structural stability, which makes them promising for application at a solar reactor level. The ceria-vanadia mixed-phase material is suitable for manufacturing reticulated porous ceramics in a dual-scale porous configuration by extension of the method presented.