(560bs) Mesoporous Silica Supported Perovskite Oxide for Low Temperature Thermochemical CO2 Conversion

Today, carbon dioxide (CO₂) emission levels are higher than at any other point in human history, and chemical reactions can be used to establish a synthetic carbon cycle, which would reduce emissions and produce liquid fuel. The reverse water-gas shift chemical looping process (RWGS-CL) is a reaction of interest because it is effective for converting large amounts of CO₂ and the resulting carbon monoxide (CO) can be used to produce hydrocarbons that are liquid fuel or chemical intermediates. Perovskite oxides are an effective catalyst for the RWGS-CL based on converting CO₂ to CO at efficient conversion temperatures, ability to form oxygen vacancies, and structural stability. The perovskite oxide used is La_0.75Sr_0.25FeO₃ (LSF). Recent studies have shown silica (SiO₂) as the most efficient support material for the perovskite oxide catalyst used in RWGS-CL. The form of SiO₂ that has been experimented with to provide support for LSF is SBA-15, because of its large pore volume and surface area, coupled with potential to support smaller particles of the perovskite increasing the number of active sites available, which would enhance conversion. Here we have analyzed adaptations to the synthesis procedure of perovskite oxides and SBA-15 to develop a single synthesis procedure for a composite material. These materials are characterized by X-ray Diffraction, N₂-physisorption, and temperature-programmed reduction, oxidation, and RWGS-CL experiments.