Monolithic mesophase silica with large ordering domains

Two-dimensional X-ray diffraction (XRD) analyses of transparent mesoscopica lly ordered silica/ block copolymer composite monoliths reveal single-cryst al-like patterns that correspond to well-ordered hexagonal domains that are greater than 1 cm x 1 mm x 1 mm in size. Analyses of the diffraction patte rns reveal highly uniform hexagonal domains with narrow distributions of or ientational order that are characterized by a phi-mosaic smaller than 2 deg rees in the plane of the hexagonal lattice and a chi-mosaic smaller than 11 degrees along the cylindrical aggregate axes. XRD and TEM results also sho w that the composite monoliths have large well-ordered cubic mesophase doma ins in the meniscus regions of the samples. Boundaries between the hexagona l and cubic domains in the monoliths reflect gradual transitions between th e two epitaxially related structures. Such large single-domain hexagonal an d cubic mesostructures were furthermore preserved following removal of the organic species by calcination to produce mesoporous silica monoliths.