title: Synthesis of hollow silica spheres with mesostructured shell using cationic-anionic-neutral block copolymer ternary surfactants.
abstract: Hollow silica spheres with mesostructured shells (HSSMS) were prepared with a vesicle template of cetyltrimethylammonium bromide-sodium dodecyl sulfate-Pluronic P123 (C(16)TMAB-SDS-EO(20)PO(70)EO(20)) at a SDS/C(16)TMAB ratio of 0.6-0.8 following a fast silicification in dilute silicate solution at pH approximately 5.0. The mesostructure of the shell is disordered, and the mesopore size is about 5.5-7.5 nm. Moreover, the direction and length of the nanochannels of the shell change with the SDS/C(16)TMAB ratios. A bi-template model, in which the C(16)TMA(+)-DS(-) form the stable bilayer vesicle structure and the P123 copolymers anchored on C(16)TMA(+)-DS(-) vesicle act as the template for the mesoporous silica, was proposed to explain the formation of the HSSMS. This bi-template model can be applied extensively to prepare the HSSMS with different diameters and pore sizes by using other C(n)TMAX-SDS-EO(n)PO(m))EO(n) ternary-surfactant mixtures.
authors.affiliation: Department of Chemistry, National Cheng Kung University, Tainan, Taiwan 701.
authors.forename: Yi-Qi
authors.initials: YQ
authors.lastname: Yeh
authors.forename: Bi-Chang
authors.initials: BC
authors.lastname: Chen
authors.forename: Hong-Ping
authors.initials: HP
authors.lastname: Lin
authors.forename: Chih-Yuan
authors.initials: CY
authors.lastname: Tang