Mesoporous silica prepared by modified true liquid crystal templating method with high thermal stability and 10-year shelf life

Abstract

We prepared mesoporous silicon dioxide with high thermal stability via modified true liquid crystal templating (TLCT). The structure of this material could withstand multiple calcination processes at 570 °C for 104 h. The material is sturdy, and it has maintained the mesoporous structure for 10 years so far. Further, it has a high Brunauer–Emmett–Teller (BET) surface area (1280 m2 g−1), exceeding 1000 m2 g−1, which was the maximum surface area produced by the original TLCT method. The material was characterized by employing the N2 sorption method, X-ray diffraction analysis, high-resolution transmission electron microscopy, X-ray photoelectron spectrometry, and 29Si magic angle spinning-nuclear magnetic resonance analysis. The 29Si MAS-NMR of the solid sample revealed that the Q4 value [Si(SiO)4] increased in direct proportion to the heat treatment duration, indicating that the condensation process continued even after multiple heat treatments. This also means that our material not only is thermally stable but also continues to improve with multiple heat treatments. Therefore, our mesoporous material is promising for use as a host in nanoparticle/cluster gusset synthesis that requires heat treatments and as an absorbent of sulfur compounds in oil products.