Synthesis of MCM-41 with a Phosphonium Template

Cetyltrimethyl phosphonium bromide was successfully used as a template in the synthesis of MCM-41. The material was characterized by small-angle X-ray diffraction, transmission electron microscopy, nitrogen adsorption, and 29 Si, 13 C, and 31 P solid-state NMR spectroscopy. These results were compared with those of MCM-41 prepared with the conventional cetyltrimethylammonium bromide surfactant showing that the material is highly ordered. Interestingly, the materials showed a “temporary” hydrothermal stability induced by residual P 2 O 5 produced by the calcination. NMR measurements on the reaction mixture showed that 31 P can be used as an excellent probe for in situ investigation of the formation mechanism.