Effects of different amounts of APTES on physicochemical and structural properties of amino-functionalized MCM-41-MSNs

Mesoporous silica nanoparticles (MSNs) are frequently functionalized to be used for specific applications, including catalysis and biomedical engineering. In this research, MCM-41-MSNs were synthesized by the sol-gel method and were functionalized with different quantities of (3-aminopropyl) triethoxysilane (APTES) using a post-grafting method to determine the physicochemical and structural changes in the MSNs. The functionalized materials were assessed by different characterization techniques, namely, TGA, FTIR, BET, SEM, TEM, DLS, zeta potential, SAXS, XRD and XPS. The FTIR data confirmed the presence of amino groups on the MSN surfaces, and the results from the XPS, TGA and zeta potential demonstrated that the APTES concentration during post-grafting directly affects the quantity of amino groups bound to the MSNs. The SAXS, TEM and nitrogen adsorption-desorption analyses showed that as the amount of APTES in the MSNs increases, the mesoporous structure become more disordered. [GRAPHICS] .