Direct Synthesis of Porous Pure and Thiol-Functional Silica Spheres through the S+X-I+ Assembly Pathway

Thiol-functional porous silica spheres with 100-μm mean diameter were synthesized in one quick step for ca. 60 min at room temperature using 1-alkylamine templating through the S + X - I + assembly pathway under an acidic condition. Thiol groups were introduced into materials while mesoporous silica spheres were prepared. SEM observation revealed that dodecylamine templating afforded a higher particle-shape quality than octylamine templating. Pore size and surface hydrophilicity of organic-functional silica spheres systematically decreased with increasing coverage of thiol groups on the pore surface, but the specific area was relatively constant. Thiol-functionalized silica spheres with 40% thiol loading resulted in microporous materials with hydrophobic pore surfaces for water vapor adsorption.