Silicon oxynitrides of KCC-1, SBA-15 and MCM-41 for CO2 capture with excellent stability and regenerability

Abstract

We report the use of silicon oxynitrides as novel adsorbents for CO₂ capture. Three series of functionalized materials based on KCC-1, SBA-15 and MCM-41 with Si–NH₂ groups were prepared using a simple one-step process via thermal ammonolysis using ammonia gas, and they demonstrated excellent CO₂ capture capabilities. These materials overcome several limitations of conventional amine-grafted mesoporous silica. They offer good CO₂ capture capacity, faster adsorption–desorption kinetics, efficient regeneration and reuse, more crucially excellent thermal and mechanical stability even in oxidative environments, and a clean and green synthesis route, which allows the overall CO₂ capture process to be practical and sustainable.