Anion Effect on Surface Density of Silanolate Groups in As-Synthesized Mesoporous Silicas

Anions present in the synthesis gel (X = F -, Cl -, Br -, NO 3 -, and SO 4 2 - ) partly remain in the channels of mesoporous templated silicas prepared in basic media. Their lyotropic character and their concentration control the silanolate group (⋮SiO - ) density at the surfactant−inorganic interface through the electrical charge neutrality, implicating the positive charges of the templating self-assembled surfactants, S + . Accordingly, the well-accepted {S + I - } generic pathway should be better referred as to {S +, m X -, (1 − m )I - }.