Surface functionalization of porous materials with sulfonic acid (SO₃H) groups is of particular interest in applications involving ion exchange, acidic catalysis and proton conduction. Macro-mesoporous silica monoliths are ideal support structures for these applications, as they combine advection-dominated mass transport in the macropores with short diffusion lengths and a large surface area (available for functionalization) in their mesoporous skeleton. Here, we report on SO₃H functionalized sol–gel silica monoliths with bimodal pore systems exhibiting macro- and mesoporosity, prepared according to a simple, efficient in situ synthesis protocol. Based on the co-condensation approach, thiol groups were introduced homogeneously into the pore structure, followed by their oxidation to SO₃H groups and the simultaneous removal of the template. The macropore size, specific surface area, and coverage with SO₃H groups are easily adjusted in this synthesis route. Importantly, the hybrid monoliths have a substantially narrower mesopore size distribution (relative standard deviation ~25%) than conventional sol–gel materials (>40%) and can be engineered crack-free in a robust column design (suitable for high-pressure flow-through operation) with mean mesopore size down to ~7 nm. They are characterized by IR spectroscopy, thermogravimetry, and elemental analysis as well as ¹³C and ²⁹Si solid state NMR to corroborate the simple, efficient combination of sol–gel-based material synthesis, surface functionalization, and template removal (i.e., polymer extraction). Complementary, inverse gas chromatography is presented as a new approach to characterize the incorporated SO₃H groups via surface energy analysis and particularly resolve changes in the Lewis acid–base characteristics engendered by that functionalization.

在涉及离子交换，酸性催化和质子传导的应用中，具有磺酸（SO ₃ H）基团的多孔材料的表面功能化特别受关注。大孔介孔二氧化硅整料是这些应用的理想支撑结构，因为它们结合了在大孔中以对流为主的质量传输，在其介孔骨架中具有短扩散长度和大表面积（可用于功能化）的特点。在这里，我们报道了根据简单，有效的原位合成方案制备的具有双峰孔系统的具有双峰孔隙系统的SO ₃ H官能化溶胶-凝胶二氧化硅单块。基于共缩合方法，将巯基均匀地引入孔结构中，然后氧化为SO_3个H组并同时移除模板。在该合成路线中，大孔尺寸，比表面积和SO ₃ H基团的覆盖率易于调节。重要的是，杂化整料的中孔尺寸分布（相对标准偏差约为25％）比传统的溶胶-凝胶材料（> 40％）要窄得多，并且可以通过坚固的色谱柱设计（适用于高压流）进行无裂纹设计。 -通孔操作）的平均中孔尺寸降低至〜7 nm。它们的特征在于红外光谱，热重分析和元素分析以及¹³ C和²⁹Si固态NMR证实了基于溶胶-凝胶的材料合成，表面功能化和模板去除（即，聚合物提取）的简单有效组合。互补的反相气相色谱法是一种通过表面能分析表征掺入的SO ₃ H基团的新方法，特别是解决了该功能化导致的路易斯酸碱特性的变化。