Oxygen‐Enhanced Crystallization of Solution‐Derived 12CaO·7Al2O3

12CaO·7Al2O3 (C12A7) composed of nanosize cage structure can clathrate oxygen radicals (O−) and has a high potential to application of strong oxidizing catalysis. In the present report, we demonstrate a fabrication route to C12A7 fine powders by Chemical Solution Deposition method in order to enhance the catalytic reactivity. Aluminum sec-butoxide, calcium nitrate tetrahydrate, acetylacetone, 2-methoxyethanol, and nitric acid were used as raw materials. Precursor solution was dried and annealed at 800°–900°C in air or O2 atmosphere. Crystalline C12A7 powders were obtained by annealing at 900°C in O2 atmosphere. Scanning electron microscope and transmission electron microscope images of the obtained powders revealed C12A7 particles were sintered and formed several micrometer particles with many pores. BET specific surface area of the powders was 4.2 m2/g. Possibility for synthesizing C12A7 powder with higher specific surface area by the solution process was indicated.

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