title: Photocatalytic Surface-Initiated Polymerization on TiO2 toward Well-Defined Composite Nanostructures.
abstract: We demonstrate the use of TiO2 nanospheres as the photoinitiator for photocatalytic surface-initiated polymerization for the synthesis of various inorganic/polymer nanocomposites with well-defined structures. The excitation of TiO2 by UV-light irradiation produces electrons and holes which drive the free radical polymerization near its surface, producing core/shell composite nanospheres with eccentric or concentric structures that can be tuned by controlling the surface compatibility between the polymer and the TiO2. When highly porous TiO2 nanospheres were employed as the photoinitiator, polymerization could disintegrate the mesoporous framework and give rise to nanocomposites with multiple TiO2 nanoparticles evenly distributed in the polymer spheres. Thanks to the well-developed sol-gel chemistry of titania, this synthesis is well-extendable to the coating of the polymers on many other substrates of interest such as silica and ZnS by simply premodifying their surface with a thin layer of titania. In addition, this strategy could be easily applied to coating of different types of polymers such as polystyrene, poly(methyl methacrylate), and poly(N-isopropylacrylamide). We expect this photocatalytic surface-initiated polymerization process could provide a platform for the synthesis of various inorganic/polymer hybrid nanocomposites for many interesting applications.
authors.affiliation: Department of Chemistry, School of Science, Beijing Jiaotong University , Beijing 100044, People's Republic of China.|Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Qipeng
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Xuefei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Jibong
authors.initials: J
authors.lastname: Joo
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Dahl
authors.affiliation: Department of Chemistry, School of Science, Beijing Jiaotong University , Beijing 100044, People's Republic of China.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.affiliation: Center for Materials Chemistry, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710054, People's Republic of China.
authors.forename: Chuanbo
authors.initials: C
authors.lastname: Gao
authors.affiliation: Department of Chemistry, University of California , Riverside, California 92521, United States.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Yin
keywords: core/shell nanostructure; inorganic/polymer nanocomposites; photocatalytic polymerization; polymer coating; titania nanospheres