Crystallization of an Ordered Mesoporous Nb–Ta Oxide

The ordered pore structure of 2D hexagonally ordered mesoporous niobium and tantalum mixed oxide has been successfully preserved during crystallization by filling the pores of the precursor with carbon prior to crystallization. Subsequent thermal treatment in an inert atmosphere produces the crystallized product without loss of the ordered mesoporous structure, and the carbon template is removed by calcination in air. Transmission electron microscopy and electron diffraction analyses clarify the preservation of the 2D hexagonally ordered mesoporous structure in single-crystal domains of about 100 nm.