A well-defined mesoporous amine silica surface via a selective treatment of SBA-15 with ammonia

摘要

2D double-quantum ~1H-~1H NMR unambiguously shows that the "isolated" ≡ Si-OH surface silanols of dehydroxylated SBA-15 are converted upon treatment with ammonia into single silylamine surface site ≡Si-NH_2. The "gem" di-silanols (≡Si(OH)_2) remain intact. Treatment using HMDS produces (≡Si(OSiMe_3)_2) but leaves ≡Si-NH_2 untouched. The resulting surface is hydrophobic and stable.