Fabrication and characterization of mesoporous borosilicate glasses with different boron contents

A series of wormhole-like mesoporous borosilicate glasses (MBSGs) with different compositions has been prepared by a combination of surfactant templating, sol-gel methods, and evaporation-induced self-assembly processes. Small-angle x-ray diffraction, high-resolution transmission electron microscopy, and N₂ sorption isotherms analysis showed that all the MBSGs prepared possess the mesoporous structure. However, the stability of the mesoporous structure is strongly affected by the boron contents. When boron content was increased, boric acid was found in the final product, and the mesoporous structure was partially degraded. The formation and loss of boric acid through the whole process may account for the partial collapse of the mesostructure.