Synthesis and solid-state NMR characterization of cubic mesoporous silica SBA-1 functionalized with sulfonic acid groups

► SBA-1 functionalized with -SO3H groups has been prepared and characterized. ► The status of the incorporated -SH groups was monitored by using 13C NMR technique. ► The transformation of -SH to -SO3H groups was achieved via oxidation with H2O2. ► 29Si{1H} HETCOR NMR revealed that the -SO3H groups are in close proximity to Q3.