title: Live Templates of a Supramolecular Block Copolymer for the Synthesis of Ordered Nanostructured TiO2Films via Guest Exchange.
abstract: In this work, we introduce a facile method based on host-guest chemistry to synthesize a range of nanostructured TiO2materials using supramolecular templates of a dendron-jacketed block copolymer (DJBCP). The DJBCP is composed of amphiphilic dendrons (4'-(3,4,5-tridodecyloxybenzoyloxy)benzoic acid, TDB) selectively incorporated into a P4VP block of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) via hydrogen bonding. The PS-b-P4VP host acts as a structure-directing template, while the guest molecules (TDB) assist the self-assembly nanostructures and zone-axis alignment, resulting in the nanostructured template of vertically oriented cylinders formed via successive phase transformations from Im3̅m to R3̅m to P6mm upon thermal annealing in the doctor-blade-cast film. The guest molecules subsequently direct the titania precursors into the P4VP domains of the templates via supramolecular guest exchange during immersion of the film in a designated precursor solution containing a P4VP-selective solvent. The subsequent UV irradiation step leads to the formation of PS-b-P4VP/TiO2hybrids. Finally, removal of the host template by calcination leaves behind mesoporous channels and makes sacrifices to be a carbon source for carbon-doping TiO2materials. Various TiO2nanoarchitectures, namely, vertical and wiggly micrometer-length channels, inverse opals, fingerprint-like channels, heterogeneous multilayers, and nanotubes, have been fabricated by highly tunable DJBCP nanostructures.
authors.affiliation: National Synchrotron Radiation Research Center , Hsinchu, 30076, Taiwan.
authors.forename: Wei-Tsung
authors.initials: WT
authors.lastname: Chuang
authors.affiliation: Department of Chemical and Materials Engineering, National Central University , Taoyuan 32001, Taiwan.
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Hsu
authors.affiliation: Department of Materials and Optoelectronic Science, Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University , Kaohsiung 80424, Taiwan.
authors.forename: En-Li
authors.initials: EL
authors.lastname: Lin
authors.affiliation: Department of Materials and Optoelectronic Science, Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University , Kaohsiung 80424, Taiwan.
authors.forename: I-Ming
authors.initials: IM
authors.lastname: Lin
authors.affiliation: Department of Chemical and Materials Engineering, National Central University , Taoyuan 32001, Taiwan.
authors.forename: Ya-Sen
authors.initials: YS
authors.lastname: Sun
authors.affiliation: Department of Materials and Optoelectronic Science, Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University , Kaohsiung 80424, Taiwan.
authors.forename: Yeo-Wan
authors.initials: YW
authors.lastname: Chiang
authors.affiliation: National Synchrotron Radiation Research Center , Hsinchu, 30076, Taiwan.
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Su
authors.affiliation: National Synchrotron Radiation Research Center , Hsinchu, 30076, Taiwan.
authors.forename: Yao-Chang
authors.initials: YC
authors.lastname: Lee
authors.affiliation: National Synchrotron Radiation Research Center , Hsinchu, 30076, Taiwan.|Department of Chemical Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: U-Ser
authors.initials: US
authors.lastname: Jeng
keywords: block copolymers; dendrons; guest exchange; mesoporous films; vertical channels