'Tubules-within-a-tubule' hierarchical order of mesoporous molecular sieves in MCM-41
Journal
Science
Journal Volume
273
Journal Issue
5276
Pages
765-768
Date Issued
1996
Author(s)
Lin, H.-P.
Abstract
The recently discovered mesoporous aluminosilicate MCM-41 consists of hexagonal arrays of nanometer-sized cylindrical pores. It is shown that this material can be synthesized by cooperative condensation of silicate and cylindrical cationic micelles. Careful control of the surfactant-water content and the rate of condensation of silica at high alkalinity resulted in hollow tubules 0.3 to 3 micrometers in diameter. The wall of the tubules consisted of coaxial cylindrical pores, nanometers in size, that are characteristic of those of MCM-41. The formation of this higher order structure may take place through a liquid crystal phase transformation mechanism involving an anisotropic membrane-to-tubule phase change. The hierarchical organization of this 'tubules-within-a-tubule' particle texture is similar to that of the frustules of marine diatoms.
SDGs
Other Subjects
aluminum; silicon dioxide; surfactant; anisotropy; article; chemical structure; crystal structure; phase transition; polymerization; priority journal; scanning electron microscopy; transmission electron microscopy; water content; X ray diffraction; Bacillariophyta; Nitzschia alba
Type
journal article