Session: 06-02 Materials and Fundamentals

Paper Number: 113581

113581 - High Flux Solar-Driven Thermogravimetric Analysis of Candidate Redox Materials Synthesized via Replica Foam Method 

Solar-driven redox cycling of non-stoichiometric metal oxides has been shown to be a promising pathway for thermochemically splitting H₂O (or CO₂) to produce solar H₂ (or CO). Often, redox materials are not characterized under high flux radiative conditions, where morphology can have an impact on reaction rates due to radiative heat transfer limitations. In an effort to understand the impact that porosity and strut thickness of foamed structures have on reduction and oxidation rates, cerium dioxide (CeO₂) and La-Sr-Mn (LSM) based perovskite porous foams were manufactured with a range of porosity and strut thicknesses using the replica method and tested in a solar simulator driven thermogravimetric analyzer (solar-TGA). Mass changes and residual product gases were measured during reduction under an Ar sweep gas and oxidation under CO₂, as well as several spatially distributed temperatures through the lower section of the foams. A xenon-arc lamp housed in a truncated ellipsoidal reflector was utilized to supply radiation ranging from concentrations of 300 suns to 1000 suns during oxidation and reduction, respectively, indirectly controlling sample temperature. Candidate perovskite samples were cycled up to 25 times to demonstrate redox stability and mechanical integrity. Results from this study provide a basis for the morphological design of future scaled-up utilization of the LSM based replica foam for efficient thermochemical splitting of H₂O.

Presenting Author: Dylan McCord University of Florida

Presenting Author Biography: Dylan graduated with his B.S. in Mechanical Engineering in 2019 from the University of North Florida. He earned his M.S. in Mechanical Engineering, specializing in fluid dynamics and thermal science, from the University of Florida in 2022. Currently, he is pursuing a Ph.D. in Mechanical Engineering at the University of Florida, studying pathways to renewable fuel sources through the use of solar thermal energy in the University of Florida's Renewable Energy Conversion Laboratory.