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DOE OSTI · 22012045

Organized thiol functional groups in mesoporous core shell colloids

Marchena, Martin H·Granada, Mara·Bordoni, Andrea V·Joselevich, Maria·Troiani, Horacio·Williams, Federico J·Wolosiuk, Alejandro
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Abstract

The co-condensation in situ of tetraethoxysilane (TEOS) and mercaptopropyltrimethoxysilane (MPTMS) using cetyltrimethylammonium bromide (CTAB) as a template results in the synthesis of multilayered mesoporous structured SiO{sub 2} colloids with 'onion-like' chemical environments. Thiol groups were anchored to an inner selected SiO{sub 2} porous layer in a bilayered core shell particle producing different chemical regions inside the colloidal layered structure. X-Ray Photoelectron Spectroscopy (XPS) shows a preferential anchoring of the -SH groups in the double layer shell system, while porosimetry and simple chemical modifications confirm that pores are accessible. We can envision the synthesis of interesting colloidal objects with defined chemical environments with highly controlled properties. - Graphical abstract: Mesoporous core shell SiO{sub 2} colloids with organized thiol groups. Highlights: Black-Right-Pointing-Pointer Double shell mesoporous silica colloids templated with CTAB. Black-Right-Pointing-Pointer Sequential deposition of mesoporous SiO{sub 2} layers with different chemistries. Black-Right-Pointing-Pointer XPS shows the selective functionalization of mesoporous layers with thiol groups.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYBROMIDESCOLLOIDSDEPOSITIONLAYERSNANOSTRUCTURESPARTICLESPOROUS MATERIALSSHELLSSILICASILICON OXIDESSYNTHESISTHIOLSX-RAY PHOTOELECTRON SPECTROSCOPY

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Marchena, Martin H, Granada, Mara, Bordoni, Andrea V, Joselevich, Maria, Troiani, Horacio, Williams, Federico J, Wolosiuk, Alejandro. 2012-03-15. Organized thiol functional groups in mesoporous core shell colloids. https://doi.org/10.1016/j.jssc.2011.12.028

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