1 research outputs found
Facile Large-Scale Synthesis of Monodisperse Mesoporous Silica Nanospheres with Tunable Pore Structure
Mesoporous silica nanoparticles (MSNs) are experiencing
rapid development
in the biomedical field for imaging and for use in heterogeneous catalysis.
Although the synthesis of MSNs with various morphologies and particle
sizes has been reported, synthesis of a pore network with monodispersion
control below 200 nm is still challenging. We achieved this goal using
mild conditions. The reaction occurred at atmospheric pressure with
a templating solāgel technique using cetyltrimethylammonium
(CTA<sup>+</sup>) as the templating surfactant and small organic amines
(SOAs) as the mineralizing agent. Production of small pore sizes was
performed for the first time, using pure and redispersible monodispersed
porous nanophases with either stellate (ST) or raspberry-like (RB)
channel morphologies. Tosylate (Tos<sup>ā</sup>) counterions
favored ST and bromide (Br<sup>ā</sup>) RB morphologies at
ultralow SOA concentrations. Both anions yielded a worm-like (WO)
morphology at high SOA concentrations. A three-step formation mechanism
based on self-assembly and ion competition at the electrical palisade
of micelles is proposed. Facile recovery and redispersion using specific
SOAs allowed a high yield production at the kilogram scale. This novel
technique has practical applications in industry