Semi-fluorinated Surfactant Syntheses of Ordered Porous Materials with Tailorable Pore Sizes
journal contributionposted on 14.12.2004, 00:00 by Xiangju Meng, Yan Di, Lan Zhao, Dazhen Jiang, Shougui Li, Feng-Shou Xiao
Novel ordered mesoporous silica-based materials (JLU-14 and JLU-15) with tailorable size are successfully synthesized by changing crystallization temperatures in both strongly acidic media and neutral conditions using semi-fluorinated surfactant [FSO-100, CF3(CF2)4(EO)10] as a template. JLU-14 and JLU-15 show much higher hydrothermal and mechanical stability than those of MCM-41, which are assigned to their relatively thicker mesoporous walls. Characterization of samples by X-ray diffraction (XRD), transmission electron microscopy (TEM), and N2 adsorption shows that the pore sizes of JLU-14 and JLU-15 are estimated to vary from micropore to mesopore (1.6−4.0 nm) with various crystallization temperatures (room temperature to 100 °C). Furthermore, heteroatoms such as Ti species are effectively introduced into mesoporous silica of JLU-14 from various routes, and catalytic data show that Ti−JLU-14 assembled from preformed TS-1 nanoclusters is very active. Moreover, the semi-fluorinated surfactant syntheses are not limited to the use of FSO-100, and many semi-fluorinated surfactants are candidates only if they can effectively form regular micelles in solution. Therefore, semi-fluorinated surfactant synthesis is a new route to prepare a series of stable ordered mesoporous silica and heteroatom-incorporated silica materials with tailorable sizes.