Liquid Phase Formation of Spinel Surface Layers on Hexaaluminate Microcrystals

Abstract
Spinel oxide (Mn3O4) surface layers were produced on hexaaluminate microcrystals by means of the air-oxidation process. The surface layer completely covered the basal plane of hexagonal facets as evident from HREM observation and CO2 chemisorption measurement. The catalytic activity for methane oxidation was strongly enhanced by this modification.