Tailoring the pore-size distribution of high surface area microporous silicon imidonitrides by control of precursor composition

Abstract

High surface area, microporous, amorphous silicon imidonitride, characterized by infrared spectroscopy, MAS 29 Si NMR, surface area and porosity measurements has been prepared by thermal ammonolysis of both co-oligomers of methylsilazane and dimethylsilazanes and of block copolymers of butadiene and methylsilazane. Variation of the organic content of the silazane is a means of controlling the surface area of the resulting solid and tailoring the pore-size distribution of the final silicon imidonitride. The resulting materials have pore-size distributions showing a maximum in the range associated with wide-pore zeolites.