Ordered mesoporous silica-based materials with very high content of substituted heteroatoms from a pH-adjustor of urea

摘要

A simple and effective method is used to introduce a large amount of heteroatoms into mesoporous walls of SBA-15 such as Si/Al ratio at near 1.0. This method is based on slow hydrolyzation of urea at the temperature of ~90 °C, which makes pH value of the solution change gradually. The results of XRD, N2 isothermals, TEM, SEM, NMR and element analysis indicate that all the samples have highly ordered mesostructures with very high content of substituted heteroatoms.