title: Preparation of hollow titania nanoparticles of single-nanometer size using a PAMAM dendrimer template.
abstract: Hollow titania nanoparticles of single-nanometer size have been prepared from titanium oxysulfate (TiOSO₄) using poly(amidoamine) (PAMAM) dendrimer molecules (Generations 5 with amino terminal groups) as a template. At low pH (pH 1), hydrolysis of the titania precursor was attenuated and the sol-gel reaction preferentially proceeded at the dendrimer surface. Calcination at 450°C yielded crystalline titania nanoparticles of 5.5 nm diameter with a ~2 nm cavity. These hollow titania nanoparticles showed a larger band-gap energy than solid particles of corresponding size.
authors.affiliation: Department of Pure and Applied Chemistry, Tokyo University of Science, Yamazaki, Noda, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Sorida
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Hakoda
authors.forename: Kanjiro
authors.initials: K
authors.lastname: Torigoe
authors.forename: Takeshi
authors.initials: T
authors.lastname: Endo
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sakai
authors.forename: Hideki
authors.initials: H
authors.lastname: Sakai
authors.forename: Masahiko
authors.initials: M
authors.lastname: Abe
mesh_terms: D003460:Crystallization; D050091:Dendrimers / Q000737:chemistry; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D053758:Nanoparticles; D049329:Nanostructures; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D044367:Phase Transition; D013431:Sulfates / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D050091:Dendrimers; C104700:PAMAM Starburst; D013431:Sulfates; D014025:Titanium