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In situ characterizations of the selective CO 2 adsorption in free-template nanosized zeolites RHO and CHA. ACTA CRYSTALLOGRAPHICA SECTION A FOUNDATIONS AND ADVANCES 2022. [DOI: 10.1107/s2053273322090672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
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Formation of copper nanoparticles in LTL nanosized zeolite: spectroscopic characterization. Phys Chem Chem Phys 2018; 20:2880-2889. [PMID: 29327021 DOI: 10.1039/c7cp07650a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The state of copper species stabilized in nanosized LTL zeolite subjected to various post-synthesis treatments was unveiled by a range of spectroscopic techniques. FTIR and UV-Vis studies demonstrated that the reduction process of copper in the LTL nanosized zeolite leads to the formation of different species including Cu2+, Cu+ and Cu nanoparticles (Cu NPs). The adsorption of probe molecules (NO and CO) was used to selectively monitor the copper species in the LTL nanosized zeolite upon oxidation and reduction post-synthesis treatments. Both the Cu2+ and Cu+ species were probed by NO and CO, respectively. The amount of Cu+ in the LTL zeolite nanocrystals was about 43% as determined by FTIR, while the amount of Cu NPs was about 55% determined by the UV-Vis spectroscopic characterization. These results were complemented by EPR, 29Si and 63Cu MAS NMR spectroscopic data. The EPR spectroscopy was further applied to monitor the effective reduction of the Cu2+ species and their re-oxidation, while the 63Cu MAS NMR verified the presence of Cu NPs in the LTL nanosized zeolite crystals.
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Hydrogen positions in single nanocrystals revealed by electron diffraction. Science 2017; 355:166-169. [PMID: 28082587 DOI: 10.1126/science.aak9652] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 11/22/2016] [Indexed: 01/18/2023]
Abstract
The localization of hydrogen atoms is an essential part of crystal structure analysis, but it is difficult because of their small scattering power. We report the direct localization of hydrogen atoms in nanocrystalline materials, achieved using the recently developed approach of dynamical refinement of precession electron diffraction tomography data. We used this method to locate hydrogen atoms in both an organic (paracetamol) and an inorganic (framework cobalt aluminophosphate) material. The results demonstrate that the technique can reliably reveal fine structural details, including the positions of hydrogen atoms in single crystals with micro- to nanosized dimensions.
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Abstract
Composites consisting of fluorescein (F) entrapped inside various zeolite structures (i.e. FAU, LTL, MFI, and LTA) were prepared by catalytic synthesis of the dye from its precursors (phthalic anhydride and resorcinol) adsorbed in the zeolites.
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Zeolite Nanoparticles for Selective Sorption of Plasma Proteins. Sci Rep 2015; 5:17259. [PMID: 26616161 PMCID: PMC4663482 DOI: 10.1038/srep17259] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/23/2015] [Indexed: 12/30/2022] Open
Abstract
The affinity of zeolite nanoparticles (diameter of 8-12 nm) possessing high surface area and high pore volume towards human plasma proteins has been investigated. The protein composition (corona) of zeolite nanoparticles has been shown to be more dependent on the plasma protein concentrations and the type of zeolites than zeolite nanoparticles concentration. The number of proteins present in the corona of zeolite nanoparticles at 100% plasma (in vivo state) is less than with 10% plasma exposure. This could be due to a competition between the proteins to occupy the corona of the zeolite nanoparticles. Moreover, a high selective adsorption for apolipoprotein C-III (APOC-III) and fibrinogen on the zeolite nanoparticles at high plasma concentration (100%) was observed. While the zeolite nanoparticles exposed to low plasma concentration (10%) exhibited a high selective adsorption for immunoglobulin gamma (i.e. IGHG1, IGHG2 and IGHG4) proteins. The zeolite nanoparticles can potentially be used for selectively capture of APOC-III in order to reduce the activation of lipoprotein lipase inhibition during hypertriglyceridemia treatment. The zeolite nanoparticles can be adapted to hemophilic patients (hemophilia A (F-VIII deficient) and hemophilia B (F-IX deficient)) with a risk of bleeding, and thus might be potentially used in combination with the existing therapy.
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Silver confined within zeolite EMT nanoparticles: preparation and antibacterial properties. NANOSCALE 2014; 6:10859-10864. [PMID: 25117582 DOI: 10.1039/c4nr03169e] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The preparation of pure zeolite nanocrystals (EMT-type framework) and their silver ion-exchanged (Ag(+)-EMT) and reduced silver (Ag(0)-EMT) forms is reported. The template-free zeolite nanocrystals are stabilized in water suspensions and used directly for silver ion-exchange and subsequent chemical reduction under microwave irradiation. The high porosity, low Si/Al ratio, high concentration of sodium and ultrasmall crystal size of the EMT-type zeolite permitted the introduction of a high amount of silver using short ion-exchange times in the range of 2-6 h. The killing efficacy of pure EMT, Ag(+)-EMT and Ag(0)-EMT against Escherichia coli was studied semi-quantitatively. The antibacterial activity increased with increasing Ag content for both types of samples (Ag(+)-EMT and Ag(0)-EMT). The Ag(0)-EMT samples show slightly enhanced antimicrobial efficacy compared to that of Ag(+)-EMT, however, the differences are not substantial and the preparation of Ag nanoparticles is not viable considering the complexity of preparation steps.
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Corona protein composition and cytotoxicity evaluation of ultra-small zeolites synthesized from template free precursor suspensions. Toxicol Res (Camb) 2013. [DOI: 10.1039/c3tx50023c] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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Nanosized MEL zeolite and GeSe2 chalcogenide layers as functional building blocks of tunable Bragg stacks. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm34351g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Prospects and challenges in the synthesis of zeotype materials. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311096929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Preparation of Colloidal BEA Zeolite Functionalized with Pd Aggregates as a Precursor for Low Dimensionality Sensing Layer. ACTA ACUST UNITED AC 2010. [DOI: 10.1166/sl.2010.1301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Investigation of the light induced redistribution of zeolite Beta nanoparticles in an acrylamide-based photopolymer. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1464-4258/11/2/024016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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13
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Zeolite beta films synthesized from basic and near-neutral precursor solutions and gels. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2005. [DOI: 10.1016/j.msec.2005.07.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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Nondestructive Identification of Colloidal Molecular Sieves Stabilized in Water. J Phys Chem B 2005; 109:17060-5. [PMID: 16853175 DOI: 10.1021/jp051413v] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The encapsulation of small quaternary ammonium ions in zeolite frameworks could be used as a base for investigation of the crystallization process of colloidal (nanosized) molecular sieves stabilized in water with Raman and (13)C NMR spectroscopic methods. The organic-framework interactions in colloidal microporous materials with LTA, FAU, BEA, and MFI topology have been considered; the results show that the crystallinity of nanosized particles with monomodal particle size distribution stabilized in water can be examined using the vibrational and magnetic resonance spectral features of the organic template molecules occluded in the specific pores and cages in the zeolite framework. The molecular packing effect and restricted mobility due to specific organic/framework interactions result in shifts and substantial broadening of the (13)C NMR signals, as well as in changes of the positions and the relative intensities of the Raman peaks. The spectroscopic methods are very efficient for analyzing the crystalline structures of nanosized molecular sieves stabilized in aqueous suspensions due to no restrictions related to the particle size.
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Abstract
A new synthesis method for preparation of thin films and powders consisting of zeolite beta nanocrystals embedded in ordered mesoporous silica matrix is described. The final structures possessing bimodal porosity, i.e., high degree of mesophase order and spatially defined microporous zeolite nanocrystals are obtained via simultaneous solvent evaporation of preformed silica/surfactant/ethanol/nanosized zeolite beta assemblies. The films were characterized with grazing-incident diffraction (GID), nitrogen sorption based on gravimetric measurements with quartz crystal microbalance (QCM) devices, and transmission electron microscopy (TEM). It is shown that the incorporation of beta nanocrystals in the mesoporous silica matrix and the mesophase order itself can be controlled through the variation of the fractional amounts of the zeolite nanoparticles and silica/surfactant solutions. The HR-TEM measurements showed that the nanosized Beta microporous crystals are separated and at the same time connected through an ordered mesostructured matrix.
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Advanced applications of zeolites. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0167-2991(05)80015-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
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17
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Colloidal LTL zeolite synthesized under microwave irradiation. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0167-2991(05)80316-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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Abstract
Raman spectroscopy has been applied to series of BEA- and BEC-type samples differing from each other in size, Si/Al ratio and polymorph percentage in order to analyse the effect of interlayer stacking arrangements on the vibrational modes of zeolite beta. The Raman peaks observed in the spectral range 250-550 cm-1 were assigned to the rings building the basic (001)-layer and to those linking the adjacent layers in zeolite beta. It is shown that the intensity ratio rho between the Raman signals at 314 and 343 cm-1 is most sensitive to the degree of periodicity faults along the c direction. A larger value of rho indicates a larger size of polymorph stacking sequence, i.e. improvement of the stacking faultlessness. The interlayer stacking disorder and the degree of connectivity point defects are higher in nanosized zeolite beta than in micron-sized crystals. The Al content influences the concentration of defected SiOH groups, but is less important for the interlayer stacking sequences in colloidal zeolite beta.
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Photochemistry of 2-(2‘-Hydroxyphenyl)benzothiazole Encapsulated in Nanosized Zeolites. J Phys Chem A 2004. [DOI: 10.1021/jp047924j] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nanosized gismondine grown in colloidal precursor solutions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:5271-6. [PMID: 15986662 DOI: 10.1021/la0400151] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A colloidal molecular sieve with GIS-type structure was prepared from aged aluminosilicate precursor solutions containing tetramethylammonium (TMA) hydroxide under hydrothermal treatment at 100 degrees C. The nucleation and the development of the GIS zeolite structure were studied by dynamic light scattering, scanning electron microscopy, X-ray diffraction, Raman and infrared spectroscopies, and liquid-state NMR spectroscopy. It is shown that the aging at room temperature leads to the formation of subcolloidal particles that incorporate TMA cations and form larger aggregates. After an extended heating of 13 days, a complete transformation from amorphous precursor material to crystalline GIS-type colloidal particles is observed. The mean hydrodynamic radius of the crystalline GIS particles is in the range of 30-50 nm. The specific template-framework interactions influence the spectral features of the TMA cations incorporated in the zeolite structure, thus making possible the use of the corresponding Raman spectra and 13C NMR data for the examination of the crystallinity of GIS-type colloidal particles stabilized in water.
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Functionalized cubic mesostructured silica films. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2003. [DOI: 10.1016/j.msec.2003.09.134] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Preparation of nanosized micro/mesoporous composites. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2003. [DOI: 10.1016/j.msec.2003.09.151] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Pure silica nanoscale zeolite BETA with monomodal particle size distribution was synthesized from a colloidal precursor solution and successfully applied for the preparation of hydrophobic ultrathin films on silicon wafers via spin coating.
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Fe-containing mesoporous film hosts for carbon nanotubes. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2003. [DOI: 10.1016/s0928-4931(02)00249-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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Synthesis of colloidal AlPO4-18 crystals and their use for supported film growth. ACTA ACUST UNITED AC 2003. [DOI: 10.1039/b304670m] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Crystallization of nanosized MEL-type zeolite from colloidal precursors. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2002. [DOI: 10.1016/s0928-4931(01)00452-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Crystal growth of nanosized LTA zeolite from precursor colloids. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s0167-2991(02)80032-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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Abstract
The formation and growth of crystal nuclei of zeolite A from clear solutions at room temperature were studied with low-dose, high-resolution transmission electron microscopy in field emission mode and with in situ dynamic light scattering. Single zeolite A crystals nucleated in amorphous gel particles of 40 to 80 nanometers within 3 days at room temperature. The resulting nanoscale single crystals (10 to 30 nanometers) were embedded in the amorphous gel particles. The gel particles were consumed during further crystal growth at room temperature, forming a colloidal suspension of zeolite A nanocrystals of 40 to 80 nanometers. On heating this suspension at 80 degrees C, solution-mediated transport resulted in additional substantial crystal growth.
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Influence of reactive radicals in cellulose fibres on the formation of zeolite coatings. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940002087] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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The effect of plastic deformation and thermal annealing of the copper substrate on the zeolite film formation. ACTA ACUST UNITED AC 1994. [DOI: 10.1039/c39940000979] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Structure-controlled effect of organic templates on zeolite crystallization. ACTA ACUST UNITED AC 1994. [DOI: 10.1007/bf01019469] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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36
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On the crystallization mechanism of zeolite ZSM-5: Part 2. MNDO calculations of basic characteristics of some diamines used as templates. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0144-2449(93)90010-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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On the crystallization mechanism of zeolite ZSM-5: Part 1. Kinetic compensation effect for the synthesis with some diamines. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0144-2449(93)90009-r] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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38
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A correlation between the fundamental properties of templates and the kinetics of ZSM-5 crystallization. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0144-2449(93)90068-e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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