UV Raman spectroscopic study on the synthesis mechanism and assembly of molecular sieves

Abstract

In the past decade, UV Raman spectroscopy has become a powerful technique for the characterization of the synthesis mechanism and assembly of molecular sieves. Ultraviolet excitation avoids fluorescence that plagues visible Raman spectroscopy and concurrently enhances the Raman signal because of the short wavelength of excitation and the resonance Raman effect. The advances of UV Raman spectroscopy, UV resonance Raman spectroscopy and in situ UV Raman spectroscopy and their applications to the characterization of zeolite assembly mechanisms are provided in this tutorial review. Using UV Raman spectroscopy, the synthesis mechanism of zeolites, including the identification of primary units, assembly through key intermediates, transition metal species, and the roles of the organic templates in framework formation have been elucidated, and are discussed herein.