Because the XRD patterns of each pair were almost similar, there was no significant effect of concentration and time on the crystallinity of the modified materials.
When the concentration of each silylating agent was fixed and the time was varied, similar XRD patterns were obtained. Vice versa, when the concentration was varied at each fixed modification time, similar XRD patterns were obtained as
well (spectrum not shown).
There was no difference in XRD spectrum when different silylating agents were employed.
Thus, modification of RH-MCM-41 with different silylating agents, concentrations, and aging times within our studied ranges showed insignificant affect to the material morphology.