Nanostructured organic/inorganic hybrid materials has been the subject of numerous studies because of their various applications including photovoltaics,photocatalysts,photoconductors and sensors by their optical,electrical and photocatalytic properties.1 However,it is essential that the morphology of mesoporous inorganic films be controlled to fully realize the potential of these materials. For example,in catalytic applications,the surface-to-volume ratio that is controlled by the morphology of inorganic films is an important parameter because it determines the active-site density on the surface available for surface reaction. In photovoltaic materials,the well-ordered structure on the nanometer scale should be established throughout the film to achieve efficient charge separation and charge transportation with reduced charge recombination probability.2 It is therefore key to prepare mesoporous inorganic films with well-defined,well-controlled morphologies. Among many methods to prepare mesoporous inorganic films,the template approach using the self-assembly of block copolymers have been widely employed. There have been numerous reports on excellent methods to control the block copolymer self- assembly,generating well-ordered nanostructure. In this study,we have fabricated regular mesoporous titania films by fully utilizing powerful ability of block copolymer to control the morphology on the nanometer scale. Polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymer was used as a structure-directing agent and titania isopropoxide was chosen as an inorganic precursor. Structural characterization of titania films was conducted by using a combination of atomic force microscope(AFM),field emission scanning electron microscope(FE-SEM) and grazing incidence small-angle X-ray scattering(GISAXS).
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