Synthesis of large pore-diameter SBA-15 mesostructured spherical silica and itsapplication in ultra-high-performance liquid chromatography

摘要

A modified synthesis approach for spherical large pore-diameter SBA-15 mesoporous silica (SLP-SBA-15)with particle size range of 0.5-1 p.m was being reported. It was worth mentioning that in this improvedmethodology, the use of cetyltrimethylammonium bromide (CTAB) as co-template significantly reducedthe self-assembly time from 24 h to 45 min. Moreover, under reflux condition, the reaction time could befurther shortened by reducing the aging time from 48 h to 6 h. The resultant SLP-SBA-15 was thereaftersuccessfully functionalized and packed into an ultra-high-performance liquid chromatography (UHPLC)column for the separation of aromatic compounds. A variety of characterizations demonstrated thatthe silica products exhibited a well-ordered 2d hexagonal mesostructure with well-formed sphericalmorphology. pore-diameter can be enlarged up to 8.2 nm without affecting the structural order. The SLP-SBA-15 samples showed excellent thermal and hydrothermal stabilities. The octadecyltriethoxysilanefunctionalized SLP-SBA-15 (SLP-C18-SBA-15) was demonstrated to be an effective stationary phase inUHPLC application because the column exhibited significantly reduced column pressure (2800 psi) at aflow rate of 0.4 ml/min. Accordingly, it would afford greater flexibility for tuning of the flow rate to meetthe fast separation requirement