Silica hybrid nanocomposites

Abstract

Abstract:In this work we present experimental results about the formation, properties and structure of sol -gel silica based biocomposite containing Calcium alginate as an organic compound. Two different types of silicon precursors have been used in the synthesis: tetramethylortosilicate (TMOS) and ethyltrimethoxysilane (ETMS). The samples have been prepared at room temperature. The hybrids have been synthesized by replacing different quantitis of the inorganic precursor with alginate. The structure of the obtained hybrid materials has been studied by XRD, IR Spectroscopy, EDS, BET and AFM. The results proved that all samples are amorphous possessing a surface area from 70 to 290 m 2 /g. It has also been established by FT IR spectra that the hybrids containing TMOS display Van der Walls and Hydrogen bonding or electrostatic interactions between the organic and inorganic components. Strong chemical bonds between the inorganic and organic components in the samples with ETMS are present. A self-organized nanostructure has been observed by AFM. In the obtained hybrids the nanobuilding blocks average in size at about 8 -14 nm for the particles.

Synthesis of alginate‐silica hybrid hydrogel for biocatalytic conversion by β‐glucosidase in microreactor

“…Adding PDADMAC resulted in compact structures in comparison to the other formulations without PDADMAC as can be seen at magnifications of 2500 and 5000× (Fig. However, Chernev et al [44] prepared a silica based hybrid gel containing calcium alginate as an organic polymer, along with tetramethyl ortosilicate (TMOS) and ethyltrimethoxysilane (ETMS) as silica precursors and surface areas ranged from 70 to 290 m 2 /g. No aggregation was observed based on EDS/mapping images, on the contrary silica was distributed homogeneously in alginate gel, which is important for achieving appropriate porous structure.…”

“…Surface area of these aerogels were 10, 9, and 384 m 2 /g, respectively. However, Chernev et al [44] prepared a silica based hybrid gel containing calcium alginate as an organic polymer, along with tetramethyl ortosilicate (TMOS) and ethyltrimethoxysilane (ETMS) as silica precursors and surface areas ranged from 70 to 290 m 2 /g. Xu and Lee [45] synthesized hybrid silica-based monolith using TMOS as a silica precursor and modified with 3-mercaptopropyltrimethoxysilane, which yielded a surface area of 467 m 2 /g.…”

Theoretical studies on the electronic structures and spectra of single silicon-doped SWCNTs

“…Nano materials have been widely studied [1][2] since they have extraordinary magnetic [3] and optical properties [4]. The discovery of carbon nanotubes [5] is a milestone in the research of nano science and technology.…”

Sol-Gel Nanomaterials with Algal Heteropolysaccharide for Immobilization of Microbial Cells, Producing A-Galactosidase and Nitrilase

“…In our previous works we have compared pure silica matrices with inorganic-organic hybrid matrices obtained by using different inorganic precursors: tetraethylortosilicate (teoS), tetramethylortosilicate (tMoS), ethyltrimethoxysilane (etMS), methyltriethoxysilane (MteS) and an organic compound such as: polyethylene oxide (Peo), polyacrylamide gel (PAAG), ca alginate, gelatin and others (5,10,19). …”