The role of polymethylhydrosiloxane in the sol-gel synthesis of high surface area porous silicon carbide

Abstract

Abstract High surface area porous silicon carbide was synthesized via a modified sol-gel method. In the sol-gel method, furfuryl alcohol and tetraethoxysilane were used respectively as carbon and silicon precursors, polymethylhydrosiloxane (PMHS) was employed as a pore-adjusting agent for preparing a carbonaceous silica xerogel. SiC was obtained by the carbothermal reduction of the carbonaceous silica xerogel at 1 300 °C in argon flow and then purified by removing excess silica, carbon and other impurities. Depending on the amount of PMHS added in the sol-gel process, the SiC products are found to have high specific surface area ranging from 120 to 167 m2 g−1 and pore volume ranging from 0.49 to 1.01 cm3 g−1. It is therefore suggested that PMHS enhances the production of mesoporous pores in the SiC products.