Stabilization of nanosized MgFe2O4 nanoparticles in phenylene-bridged KIT-6-type ordered mesoporous organosilica (PMO)

Abstract

The unique combination of two functional materials, namely the earth-abundant spinel magnesioferrite (MgFe 2 O 4) and mesoporous phenylene-bridged KIT-6-type organosilica, was developed. The mesoporous organosilica acts as host matrix for the nanosized MgFe 2 O 4 particles which leads to better dispersibility and increased stability towards acids. Additionally, the mesoporous host is a very good material to generate a toolbox towards applicable materials due to flexible functionalization. Nanosized, monodisperse MgFe 2 O 4 crystallites were synthesized via a facile microwave assisted non-aqueous reaction path. Afterwards, the particles were embedded in phenylene-bridged periodic mesoporous organosilica with 3D cubic pore arrangement (KIT-6-type PMO) generating a new kind of mesoporous inorganic-organic hybrid material (MgFe 2 O 4 @phe-PMO). The MgFe 2 O 4 @phe-PMO exhibits the characteristics of both components: A high specific surface area of 1164 m 2 g-1 with clearly defined and highly ordered micro-and mesopores (1.5 and 6.8 nm), and the broad absorption of visible and UV light due to the phenylene bridging units in the PMO and the MgFe 2 O 4 particles. The presence of MgFe 2 O 4 nanoparticles in the PMO matrix is proven by UV/Vis spectroscopy, powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). Selected area electron diffraction (SAED) and Scanning TEM in atomic resolution was chosen to demonstrate the crystallinity and phase purity of MgFe 2 O 4 particles in the hybrid material. An additional focus was laid on calcination of the MgFe 2 O 4 /PMO hybrids to remove template molecules, while preventing rearrangement or shrinkage of the pore system and to promote further crystallization of the MgFe 2 O 4 nanoparticles.

Bi-functionalized aminoguanidine-PEGylated periodic mesoporous organosilica nanoparticles: a promising nanocarrier for delivery of Cas9-sgRNA ribonucleoproteine

“…2 f). Accordingly, these patterns agreeing with the ( Ia-3d ) symmetry and indicate the presence of well-defined pores before and after surface modification of M-PMO [ 73 , 74 ]. The observed decrease in the intensity of the reflections, without change in their position and pattern suggests the success of functionalization as well as the retention of the meso-porosity characteristic of AGu@PEG 1500 -PMO during surface modification.…”

Engineering mesoporous silica nanoparticles for drug delivery: where are we after two decades?

“…The solid is recovered and the surfactant template is removed, mostly by extraction, but due to the high thermal stability of Si-C bonds and selected organic bridges, in specific cases, using carefully established protocols, also calcination may be possible to at least partially remove the surfactant, while retaining the organic groups in the framework. 122,123 PMOs have not been as extensively studied for use in drug delivery as their pure silica counterparts (possibly modified with pending organic groups). This has been attributed to the more difficult synthesis of uniform and discrete PMO nanoparticles (NPs) with adjustable properties on the one hand, and lack of information on bio-safety of PMO nanoparticles on the other.…”

“…The solid is recovered and the surfactant template is removed, mostly by extraction, but due to the high thermal stability of Si–C bonds and selected organic bridges, in specific cases, using carefully established protocols, also calcination may be possible to at least partially remove the surfactant, while retaining the organic groups in the framework. 122,123…”

Novel antifouling nanofiltration PES membranes incorporating with C‐KIT‐6 for heavy metal ions removal

“…KIT‐6 build‐up from the three‐dimensional bicontinuous cubic structure is among mesoporous silica materials which have been used as catalyst, gas adsorbent and separator, supercapacitor, electrode, and so on 28–30 . KIT‐6 has a high surface area per volume ratio, high hydrothermal stability, large and tunable cylindrical pores with high interconnectivity and thick walls 31 . KIT‐6 has advantages over one‐dimensional and two‐dimensional mesoporous structures due to its ordered three‐dimensional pore structure with two intertwined systems of mesoporous channels providing more active sites for functionalization, more resistance to pore blocking, and more permeability without sacrificing the selectivity 32 .…”

“…[28][29][30] KIT-6 has a high surface area per volume ratio, high hydrothermal stability, large and tunable cylindrical pores with high interconnectivity and thick walls. 31 KIT-6 has advantages over one-dimensional and two-dimensional mesoporous structures due to its ordered three-dimensional pore structure with two intertwined systems of mesoporous channels providing more active sites for functionalization, more resistance to pore blocking, and more permeability without sacrificing the selectivity. 32 It has been shown that the addition of KIT-6 to the polymeric matrix enables the fabrication of intimate composites due to the penetration of polymer chains into the relatively large pores of the mesoporous.…”