Mesophase ordering and macroscopic morphology structuring of mesoporous TiO_2 film

摘要

An easy tuning of surface morphology of optically transparent TiO_2 film due to two different types of micellar packing; hexagonal structure consisting of close-packed cylindrical micelles and a cubic structure resulting from the close-packing of spherical micelles is demonstrated. By a calculable % volume fraction of block copolymer (BCP), the desired micelle crystal phase can be induced and the architectures of the polymer can be rationally tuned to effectively organize mesostructured composite solids with fairly large ordering length. P123 amphiphilic triblock copolymer PEO-PPO-PEO(EO)_(20)(PO)_(70)(EO)_(20) is used as structure-directing agents for the highly organized metal oxide framework employing the evaporation induced self-assembled (EISA) route. The mesoporous structures have a narrow pore size distributions diameter of ～10 nm, wall thickness of ～5 nm and are well-crystallized with anatase phase.