Fabrication of Mesoporous Silica Microtubules through the Self-Assembly Behavior of β-Cyclodextrin and Triton X-100 in Aqueous Solution

Mesoporous silica microtubules were hydrothermally prepared with tetraethoxysilane (TEOS) as silica source and the supramolecular assembly of β-cyclodextrin and the nonionic surfactant Triton X-100 (TX-100) as the structure-directing agent. The products exhibit a well-developed tubular morphology with diameters between 0.8 and 2 μm, wall thicknesses of 0.2−1 μm, and lengths up to 10−25 μm. The morphology and mesoporous structure of the microtubules are preserved after calcination at 550 °C for 5 h, and their pore size and Brunauer−Emmett−Teller (BET) surface area are 2.3 nm and 847 m 2 /g, respectively. The formation mechanism of mesoporous microtubules based on the bending of silica membranes is proposed to occur by a topological transformation.