Solvothermal-assisted evaporation-induced self-assembly of ordered mesoporous alumina with improved performance

Abstract

A solvothermal-assisted evaporation-induced self-assembly (SA-EISA) approach has been developed for the synthesis of ordered mesoporous alumina (OMA) materials with high thermal stability and improved performance in catalysis. In conventional EISA process, the evaporation step is accompanied by the hydrolysis of organic aluminum precursors, thus the evaporation conditions have significant influences on the reaction and the final structure of OMA. In our approach, the solvothermal treatment step promotes the complete hydrolysis of aluminum precursors and produces partially condensed cluster-like aluminum hydroxyl species, which allows the formation of OMA in a broad range of evaporation conditions. Compared to mesoporous alumina obtained by conventional EISA process, OMA materials prepared by SA-EISA approach exhibit higher specific surface area, pore volume and thermal stability. When used as supporting materials for vanadium oxide catalyst, OMA materials obtained by the SA-EISA approach exhibit excellent activity, selectivity and stability for ethylbenzene dehydrogenation with carbon dioxide as a mild oxidant. Our contribution has provided new understanding in the synthesis of OMA materials with improved performance for catalytic applications.