Pd Nanoparticles Fabricated on Organic-Group Modified Silica and its Catalytic Performance for Acetylene Hydrogenation

Aminopropyl-functionalized silica (NH2-SiO2) was obtained via a sol-gel process using tetraethoxylsilicate (TEOS) and aminopropyltriethoxysilane (APTES). Aminopropyl group contained silica was further modified with formaldehyde to achieve a novel organic group modified silica, denoted as CH2O-SiO2. Using CH2O-SiO2 as support to prepare surported Pd catalyst (denoted as Pd/M-SiO2), small Pd nanoparticles (1-2 nm) were fabricated on CH2O-SiO2 surport. Hydrogenation of acetylene is used as probe reaction to evaluate the catalytic performance of Pd/M-SiO2. The results indicate that Pd/M-SiO2 exhibits unique catalytic property, which the selectivity of ethylene increases with the increase of acetylene conversion. In-situ DRIFTS spectra of CO adsorption show that the organic groups presented on the silica affect the electronic property of the very small Pd nanoparticles, which causes the change of reaction paths of hydrogenation of acetylene over Pd/M-SiO2 compared with traditional supported Pd catalyst.

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Remarkable Enhancement In The N2- Selectivity of NH3-SCR Over The CeNb3Fe0.3/TiO2 Catalyst In The Presence of Chlorobenzene

10.21203/rs.3.rs-607574/v1 ◽

2021 ◽

Author(s):

Pengchao Zang ◽

Jun Liu ◽

Xiaoqing Liu ◽

Guojie Zhang ◽

Jianjun Chen ◽

...

Keyword(s):

Sol Gel ◽

Catalytic Performance ◽

Acid Sites ◽

Oxidation Activity ◽

In Situ Drifts ◽

Nh3 Scr ◽

Adsorbed Oxygen Species ◽

Initial Stage ◽

Lower Temperature

Abstract The simultaneous removal of NOx and dioxins is the frontier of environmental catalysis, which is still in the initial stage and poses several challenges. In this study, a series of CeNb3Fex/TiO2 (x = 0, 0.3, 0.6, and 1.0) catalysts were prepared by the sol-gel method and examined for the synergistic removal of NOx and chlorobenzene. The CeNb3Fe0.3/TiO2 catalyst exhibits an optimum catalytic performance, with an NOx conversion greater than 95 % at 260-380 °C. It also exhibited an optimal CB oxidation activity, in which CB promoted both the NOx conversion and N2 selectivity below 250 °C. Moreover, the more favourable ratios of Ce4+ to Ce3+, and plentiful surface adsorbed oxygen species are the reasons why CeNb3Fe0.3/TiO2 catalyst has better catalytic activity than other catalysts at lower temperature. Simultaneously, owing to the modulation of Fe to the redox properties of Ce and Nb, the large number of oxygen vacancies and acid sites, the CeNb3Fe0.3/TiO2 catalyst is is beneficial to NOx reduction and CB oxidation. Further, the results of in situ DRIFTS study reveal the NH3-SCR reactions over CeNb3Fex/TiO2 catalysts are mainly controlled by the L-H mechanism (< 200 °C) and E-R mechanism (> 200 °C), respectively.

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FTIR Study on the Preliminary Development of Synthesis Methods for Hydroxyapatite Modified Silica Aerogel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.799-800.493 ◽

2015 ◽

Vol 799-800 ◽

pp. 493-499 ◽

Cited By ~ 1

Author(s):

Nor Suriani Sani ◽

Nik Ahmad Nizam Nik Malek ◽

Mohammed Rafiq Abdul Kadir ◽

Halimaton Hamdan

Keyword(s):

Fourier Transform ◽

Ftir Spectroscopy ◽

Silica Aerogel ◽

Sol Gel ◽

Fourier Transform Infrared ◽

Synthesis Methods ◽

Modified Silica ◽

Ftir Study ◽

Sol Gel Process

Hydroxyapatite (HA) modified silica aerogel (SA) was synthesized based on 2 different techniques namely encapsulation andin-situvia aqueous colloidal sol-gel process. The structure of the synthesized HA modified SA have been studied using Fourier transform infrared (FTIR) spectroscopy. FTIR spectra of HA modified SA, derived fromin-situtechnique appear to be different from those of encapsulation technique and free HA, with the main difference lying in the phosphate bending absorbance. Results showed that the encapsulation technique preserved the native confirmation of HA in SA frameworks compared toin-situtechnique. It confirms that the use of an aqueous sol-gel encapsulation route provides a promising approach for the stabilization of HA in SA networks.

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Synthesis and Intermolecularly Mediated Assembly of Organic Pigment in Hybrid Coating Films

MRS Proceedings ◽

10.1557/proc-519-103 ◽

1998 ◽

Vol 519 ◽

Author(s):

Y. Yan ◽

Z. Duan ◽

D.-G. Chen ◽

S. Ray Chaudhuri

Keyword(s):

Sol Gel ◽

Hybrid Coating ◽

Hypsochromic Shift ◽

Hybrid Films ◽

Coating Films ◽

Organic Pigment ◽

Inorganic Hybrid ◽

Matrix Interactions ◽

Sol Gel Process

AbstractThe insoluble, strongly hydrogen bonded organic pigment of 3,6-bis-(4-chlorphenyl)-l,4- diketopyrrolo [3,4-c] pyrrole was transiently blocked by adding carbamate groups, and consequently incorporated into organic-inorganic hybrid matrices by a sol-gel process. The homo- (pigment-pigment) and hetero-intermolecular (pigment-matrix) interactions were found to control both the assembly and dispersion of pigment molecules in the hybrid coating films. A weaker interaction between matrices and pigment molecules results in aggregation of the carbamate pigment in the methyl-silicate films. A stronger interaction forms a homogenous dispersion and coloration of the phenyl-silicate films. The as-prepared methyl- and phenylsilicate films doped with the organic pigment were distinguished by a morphology change and a blue (hypsochromic) shift in absorption from 550 to 460 nm. Thermal treatment can remove the carbamate groups and in-situ form the organic pigment in the hybrid films.

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Fabrication of sulfonated poly(ether ether ketone)-based hybrid proton-conducting membranes containing carboxyl or amino acid-functionalized titania by in situ sol–gel process

Journal of Power Sources ◽

10.1016/j.jpowsour.2014.11.132 ◽

2015 ◽

Vol 276 ◽

pp. 271-278 ◽

Cited By ~ 50

Author(s):

Yongheng Yin ◽

Tao Xu ◽

Guangwei He ◽

Zhongyi Jiang ◽

Hong Wu

Keyword(s):

Amino Acid ◽

Sol Gel ◽

Proton Conducting ◽

Ether Ether Ketone ◽

Poly Ether Ether Ketone ◽

Sol Gel Process ◽

Ether Ketone ◽

Conducting Membranes ◽

Sulfonated Poly

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Preparation of the polymerizable titania oriented to 3D printing and the laser-induced crystallization

Rapid Prototyping Journal ◽

10.1108/rpj-03-2017-0041 ◽

2018 ◽

Vol 24 (9) ◽

pp. 1421-1427 ◽

Cited By ~ 2

Author(s):

Feng Liu ◽

Shaoai Xie ◽

Yan Wang ◽

Jianjun Yu ◽

Qinghua Meng

Keyword(s):

3D Printing ◽

Sol Gel ◽

Crystal Form ◽

Tetrabutyl Titanate ◽

Content Type ◽

Functional Additives ◽

Sol Gel Process ◽

Photosensitive Resin ◽

Induced Crystallization

PurposeThe titania (titanium dioxide) is one of the important functional additives in the photosensitive resin and encounters the problem of stabilization in the photosensitive resin for 3D printing. This study aims to achieve enhancement in stabilization by preparation of the polymerizable titania andin situlaser-induced crystallization during 3D printing.Design/methodology/approachA type of polymerizable titania (AAEM@TiO2) was designed and prepared from tetrabutyl titanate (TBT) and 2-(acetoacetoxy)ethyl methacrylate (AAEM) via the sol–gel process, which was characterized by Fourier-transform infrared (FTIR) spectra, ultraviolet–visible (UV-Vis) spectra, surface bonding efficiency (SBE) and settling height (H). AAEM acted on both bonding to the titania and polymerization with the monomer in resin for stabilization. The polymerizable titania could be converted to the pigmented titania by means of laser-induced crystallization. The photosensitive resin was then formulated on the basis of optimization and used in a stereolithography apparatus (SLA) for 3D printing.FindingsThe stabilization effect of AAEM on TiO2was achieved and the mechanism of competition in the light-consuming reactions during photocuring was proposed. The ratio of nAAEM/nTBTin AAEM@TiO2, the concentration of AAEM@TiO2and photoinitiator (PI) used in the photosensitive resin were optimized. The anatase crystal form was indicated by X-ray diffraction (XRD) and clustering of nanocrystals was revealed by scanning electron microscopy (SEM) after SLA 3D printing.Originality/valueThis investigation provides a novel method of pigmentation by preparation of the polymerizable titania andin situlaser-induced crystallization for SLA 3D printing.

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Immobilization of Candida Antarctica lipase B on epoxy modified silica by sol-gel process

Journal of Molecular Catalysis B Enzymatic ◽

10.1016/j.molcatb.2016.02.014 ◽

2016 ◽

Vol 127 ◽

pp. 76-81 ◽

Cited By ~ 16

Author(s):

Hong-Zhi Ma ◽

Xiao-Wei Yu ◽

Cong Song ◽

Qing-lan Xue ◽

Bo Jiang

Keyword(s):

Sol Gel ◽

Candida Antarctica ◽

Candida Antarctica Lipase B ◽

Candida Antarctica Lipase ◽

Modified Silica ◽

Lipase B ◽

Sol Gel Process

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PENGARUH RUTE SINTESIS TERHADAP KEEFEKTIFAN PENGIKATAN GUGUS PDETA PADA SINTESIS Fe3O4@SiO2@PDETA

Jurnal Teknosains ◽

10.22146/teknosains.36264 ◽

2019 ◽

Vol 8 (1) ◽

pp. 39 ◽

Cited By ~ 2

Author(s):

Susanto Susanto ◽

Ricka Prasdiantika

Keyword(s):

Raw Materials ◽

Sol Gel ◽

Trisodium Citrate ◽

Modified Silica ◽

X Ray ◽

Dispersion Agent ◽

Sol Gel Process ◽

Synthesis Routes ◽

Mixing Sequences ◽

Scanning Electron

Synthesis of Fe3O4@SiO2 modified with propyldiethylenetriamine (Fe3O4@SiO2@PDETA) with variation of synthesis routes have been investigated. Research was begun with synthesis of Fe3O4 using dispersion agent of trisodium citrate at coprecipitation system through stirring using ultrasonic wave. Coating magnetite with propyldiethylenetriamine modified silica was carried out through sol-gel process with two different mixing sequences of raw materials (two synthesis routes) with main materials of Fe3O4 synthesized, N-[3-(Trimethoxysilyl)propyl]-diethylenetriamine (TMSPDETA) and Na2SiO3. The products were characterized by fourier transform infrared (FTIR) spectrophotometer and scanning electron microscope-energy dispersive X-ray (SEM-EDX). Results indicate that Fe3O4@SiO2@PDETA has been synthesized succesfully. Fe3O4@SiO2@PDETA synthesized through route 1 (magnetite mixed with a mixture TMSPDETA and Na2SiO3) contains more propyldiethylenetriamine group than that of through route 2 (magnetite mixed with Na2SiO3 solution, then mixed with TMSPDETA)

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