Fast and low-temperature elimination of organic templates from SBA-15 using dielectric barrier discharge plasma

摘要

Organic templates P-123 of mesoporous SBA-15 can be effectively removed in a few minutes(4 min) by using the dielectric-barrier discharge(DBD) plasma technique at ambient pressure and low gas temperature(around 130 ℃). The mesoporous SBA-15 was characterized by FT-IR,^(29)Si solid sate NMR, TEM, XRD, TGA and N_2 adsorption/desorption isotherms. The as-made SBA-15 treated with DBD plasma exhibited a larger surface area of 790 m^2?·?g^(-1) with larger pores and microspore volume than samples prepared by using the conventional thermal calcination method(550℃ and 5 h, 660 m^2?·?g^(-1)). In addition to less shrinkage of the silica framework, the DBD-prepared SBA-15 showed significantly increased weight loss of 8.3%about 200 °C as compared with that of conventional calcination(5.5%), which is attributed mainly to the dehydroxylation by condensation of silanol groups.