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Numrering	Referens	Omslagsbild	Hitta
1.	Engström, V., et al. (författare) The effect of seed size on the growth of silicalite-1 films on gold surfaces 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 38:1, s. 51-60 Tidskriftsartikel (refereegranskat)abstract Silicalite-1 films grown on gold surfaces seeded with colloidal crystals with a size of 60, 165 and 320 nm were investigated by reflection–absorption infrared spectroscopy, scanning electron microscopy and X-ray diffraction in order to follow up the formation of nano-scale defects and to determine the optimal synthesis conditions for preparation of silicalite-1 films with a low concentration of defects. Using 60-nm-sized colloidal crystals, the seeding method was capable of producing silicalite-1 films with low concentrations of defects and with thicknesses ranging from 100 to 300 nm, which are predominantly oriented with the a-axis perpendicular to the surface. Hydrothermal treatment times of the 60-nm-seeded surfaces longer than 36 h as well as the seeding with 165 or 320 nm colloidal crystals substantially enhanced the formation of defects in the films.
2.	Ganemi, B., et al. (författare) Zeolite Cu-ZSM-5 : material characteristics and NO decomposition 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 38:2-3, s. 287-300 Tidskriftsartikel (refereegranskat)abstract Zeolite ZSM-5 (SiO2/Al2O3 ratio 53:1) ion exchanged with Cu2+ to 0%, 74% and 160% was characterized by X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Infrared (IR) spectroscopy, Electron spectroscopy for chemical analysis (ESCA) and ammonia desorption. A more limited set of data was obtained for Cu-ZSM-5-33, ion exchanged with 0%, 104% and 210% Cu2+ ions. All catalysts lose water below 100°C. More strongly bound water, approximately two molecules per Cu2+ ion, emerge at a higher temperature. This corresponds either to an incomplete hydration shell for zeolite-bound Cu2+ ions or to the decomposition of Cu(OH)2 and simultaneous reactive adsorption of copper ions on the inner surface of the zeolite. The process occurs in the same temperature range, 150-350°C, where XRD reveals rearrangements in the H-form of the catalyst. Reactions between the exchangeable cations and the zeolite appear critical for lattice changes and possibly the formation and dispersion of catalytically active centers at these temperatures. Dehydroxylation and water desorption are observed between 350°C and 450°C for H-ZSM-5. This temperature range overlaps with the light-off temperature for direct NO decomposition over Cu-ZSM-5. This coincidence can be rationalized in terms of two effects of enhanced ionic mobility and dynamics of the zeolitic framework. ESCA shows that partial reduction, cupric to cuprous, occurs as a result of annealing in the same temperature range. It has been suggested that NO-derived surface intermediates act as site blockers for the direct decomposition below the light-off temperature until destabilized by lattice movements. The lower stability and thus higher mobility of low SiO2/Al2O3 ratio ZSM-5 zeolites would then rationalize an advantage of these materials as supports in catalysts for direct NO decomposition.
3.	Hedlund, Jonas, et al. (författare) Controlling the preferred orientation in silicalite-1 films synthesized by seeding 1999 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 28:1, s. 185-194 Tidskriftsartikel (refereegranskat)abstract Single crystal silicon (100) wafers were seeded with colloidal silicalite-1 crystals and hydrothermally treated in a precursor solution to grow thin silicalite-1 films. A total of 28 experiments in eight series were investigated with SEM and XRD to evaluate the preferred orientation of the crystals constituting the films. The investigated parameters in the film formation process were seed crystal size, amount of adsorbed seed crystals and film thickness after hydrothermal treatment of the seeded substrates. In thin films, most of the crystalline material is oriented with the b-axis perpendicular to the substrate surface. In thick films, most of the crystalline material is oriented with the a-axis perpendicular to the substrate surface. The change in preferred orientation with film thickness is faster when small seeds are used. The amount of adsorbed seeds has a larger influence on the preferred orientation when large seeds are used. A mechanism explaining these trends is proposed. The choice of size and coverage of seeds can be used to control the preferred orientation of the crystals in a film of given thickness within certain limitations.
4.	Hedlund, Jonas, et al. (författare) High-flux MFI membranes 2002 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 52:3, s. 179-189 Tidskriftsartikel (refereegranskat)abstract The synthesis and evaluation of high performance MFI-type membranes is described. These systems exhibit fluxes that are one to two orders of magnitude higher than previous literature reports, with comparable selectivities, when tested for various single component gases and for mixtures of C4, C6 and xylene isomers.These materials are the result of a rational fabrication approach targeting ultra-thin, defect-free MFI films on open supports by using a two-step support masking technique and a monolayer of colloidal nucleation seeds, followed by in situ hydrothermal growth, producing a defect-free film with a thickness of 0.5 μm. Reproducibility of the membrane preparation was excellent.
5.	Lassinantti, Magdalena, et al. (författare) Faujasite-type films synthesized by seeding 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 38:1, s. 25-34 Tidskriftsartikel (refereegranskat)abstract Thin and continuous Faujasite-type films were synthesized on α-alumina wafers using a seeding technique. Surface modified wafers were seeded with colloidal zeolite Y crystals prior to film growth in a synthesis mixture. The effects of hydrothermal treatment on film thickness, morphology and preferred orientation of the crystals constituting the film were investigated using scanning electron microscopy and X-ray diffraction. During hydrothermal treatment a precipitate formed rapidly, leaving an almost clear solution in the upper part of the reactor. Experiments at 60–100°C were performed with the sample placed in the upper part of the synthesis solution. An increase in the film growth rate with increasing temperature was observed. Adsorbed seeds were shown to be oriented with the {1 1 1} pyramid, parallel to the substrate surface. A change in the orientation with film growth was noted, probably due to the attachment of secondary crystals to the growing film surface. In one experimental series, film growth was effected at the bottom of the tube at 100°C. Faster film growth and multilayered films were obtained. A decrease in the film thickness after prolonged hydrothermal treatment was observed in all experimental series. This is probably due to the dissolution of the film and formation of zeolite P in the synthesis solution. The thicknesses of the films synthesized in this work are in the range of 150–2700 nm. The films are promising candidates for use in membrane applications.
6.	Li, Q., et al. (författare) Nucleation period for TPA-silicalite-1 crystallization determined by a two-stage varying-temperature synthesis 1999 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 31:1, s. 141-150 Tidskriftsartikel (refereegranskat)abstract A two-stage-varying-temperature synthesis procedure, which involves a rapid change in temperature at some point during the course of crystallization, was applied to the synthesis of discrete colloidal particles of TPA-silicalite-1. As the duration of the period at the initial synthesis temperature was extended, the crystal concentration and ultimate crystal size varied until they were approximately equal to those obtained for a complete synthesis at the initial temperature. At this point in the crystallization, it was concluded that the nucleation stage was completed. For syntheses performed at 60, 80 and 100°C, the duration of the nucleation period determined by this method was about 100 h, between 4 and 6 h and less than 2 h, respectively. Thus, nucleation, for this system, is a continuous process, and it was found that the rate of nucleation, which is initially high, declines, throughout the nucleation period. In all cases, nucleation occurred during an induction period when little or no crystal growth was observed, which explains why the syntheses yielded a product with a rather narrow crystal size distribution. If, for the two-stage syntheses, the temperature change was made after completion of the nucleation period, the second synthesis temperature controlled only the linear growth rate of the crystals and the final yield of silicalite-1 obtained
7.	Li, Qinghua, et al. (författare) Synthesis and characterization of zoned MFI films by seeded growth 2002 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 56:3, s. 291-302 Tidskriftsartikel (refereegranskat)abstract Supported zoned and sandwiched MFI films were prepared by a two-step crystallization procedure, using seeds. In this work, a zoned MFI film is defined as one assembled by crystals propagating from the support to the film top surface with varying Al content along the length of the crystal. A sandwiched MFI film is referred to as one assembled by at least two layers of crystals. Six types of films were prepared, both zoned and sandwiched, with a high or a low Al-content in the ZSM-5 part and with varying order of the layers, i.e. ZSM-5 coated with silicalite-1 or vice versa. The films were characterized by SEM and TEM. The Al-distribution was measured by cross-sectional EDS, and the preferred orientation of the crystals could be determined by XRD. Truly zoned films are obtained when the compositional difference between the layers is relatively small, and the synthesis conditions are similar or when the first layer is silicalite-1. If the first layer is ZSM-5 and the synthesis conditions and/or the composition vary too much, a discontinuity occurs at the interface between the layers, and sandwiched film results, where nucleation of the second layer is initiated by secondary nucleation or by applying seeds.
8.	Li, Qinghua, et al. (författare) The nucleation period for crystallization of colloidal TPA-silicalite-1 with varying silica source 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 40:1-3, s. 53-62 Tidskriftsartikel (refereegranskat)abstract The effect of varying silica source on the nucleation and crystallization of TPA-silicalite-1 was investigated. A direct experimental method, involving a two-stage varying-temperature synthesis, was used to determine the nucleation period for colloidal crystals of TPA-silicalite-1 with different silica sources, including tetraethoxysilane (TEOS) and amorphous silica (Ludox TM and Ludox LS). For syntheses performed at 60°C with TEOS as silica source, the duration of the nucleation was about 72 h, and a very rapid increase in the crystal population occurred during the initial crystallization time. However, with the amorphous silica sources (Ludox TM or Ludox LS), the duration of the nucleation period was extended to about 120 h, and the nucleation profile consisted of a self-accelerating nucleation rate at the beginning of the nucleation period. The two-stage synthesis method could be used to determine the nucleation profile for the various silica sources. However, this technique overestimated the crystal concentration at the earliest stage of nucleation with amorphous silica. The use of amorphous silica gave rise to a broader crystal size distribution compared to that of TEOS. However, it was found that for both TEOS and amorphous silica the vast majority of the nucleation occurred during an induction period when little or no crystal growth was observed. In addition, Raman spectroscopy revealed structural differences between Ludox TM and Ludox LS which may account for differences in the nucleation processes observed for these two amorphous silicas.
9.	Mihailova, B., et al. (författare) Vibrational spectroscopy study of the structure of silicalite-1 films on a gold surface 1999 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 32:3, s. 297-304 Tidskriftsartikel (refereegranskat)abstract The structure of silicalite-1 films grown on seeded gold surfaces is investigated by modelling the observed changes in the infrared reflection absorption (IRRA) spectra of samples treated for different times in the synthesis solution. The results show that a gradual deformation of the five-membered silicon-oxygen rings occurs during the first 11 h of the hydrothermal treatment which leads to breaking of Si---O---Si linkages and to formation of linear defects along the c-axis. Interactions between the dislocations and the grain boundaries during the further growth of the film provoke the appearance of void spaces in the grain boundary interface which may cause incipient cracking in the silicalite-1 films on seeded gold surfaces. The range 1000-1300 cm-1 in the IRRA spectra is found to be appropriate for estimating the quality of silicalite-1 films grown on metal surfaces.
10.	Naydenov, Valeri, et al. (författare) Spherical silica macrostructures containing vanadium and tungsten oxides assembled by the resin templating method 2002 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 55:3, s. 253-263 Tidskriftsartikel (refereegranskat)abstract Silica-based spherical macrostructures containing vanadium and tungsten oxides were prepared using anion exchange resin beads as a shape-directing macrotemplate in a multi-step procedure. In a first step resin beads were treated with a clear and homogeneous TPA-silicate synthesis solution at 170 °C for three different times and resin-silicate composites were obtained. Short treatment times resulted in amorphous silica whereas the longest time yielded highly crystalline silicalite-1. In a second step anionic vanadium or tungsten species were introduced into the resin-silicate composites by utilization of the residual ion exchange capacity of the resin. In a final step the ion exchange resin was removed by calcination leaving behind vanadium- or tungsten-containing silica spheres. The influence of the concentration and the pH of the solutions used for vanadium and tungsten ion exchange on the properties of the final spheres was investigated. The product particles were extensively characterized by XRD, SEM, AAS, nitrogen adsorption measurements, Raman and UV–vis diffuse reflectance spectroscopy. Generally, the nature of the metal species formed within the spheres was isolated and highly dispersed monomers in tetrahedral coordination in amorphous samples and V2O5 or WO3 crystallites in crystalline ones.
11.	Qinghua, Li, et al. (författare) Aging effects on the nucleation and crystallization kinetics of colloidal TPA-silicalite-1 2001 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 43:1, s. 51-59 Tidskriftsartikel (refereegranskat)abstract A direct experimental method, involving a two-stage varying-temperature synthesis, was utilized to investigate the effects of aging on the nucleation kinetics for the synthesis of nanosized TPA-silicalite-1 with various silica sources, including tetraethoxysilane (TEOS) and amorphous silica Ludox TM. For TEOS aging had only a mild influence on the nucleation and crystallization kinetics, whereas for Ludox TM dramatic changes occurred. After extended aging periods, the nucleation kinetics for syntheses with Ludox TM became similar to those for syntheses with TEOS, leading to increasing similarities in the properties of the products of the crystallization. Independent of aging time and silica source, the nucleation processes occurred over a substantial period of time, extending over the induction period, but were completed before crystal growth was detected. With increased aging, the nucleation period was gradually decreased and tended to be completed earlier in the induction period. Raman spectra revealed that with Ludox TM, aging enhanced the interaction between TPA+ and the silica species, leading to an increase in the concentration of precursor species for nucleation, which in turn accelerated the nucleation rate.
12.	Schoeman, Brian J. (författare) Analysis of the nucleation and growth of TPA-silicalite-1 at elevated temperatures with the emphasis on colloidal stability 1998 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 22:1-3, s. 9-22 Tidskriftsartikel (refereegranskat)abstract The question as to whether silicalite-1 grows via an aggregation of smaller particles or similar sized particles has been addressed by considering the fundamentals governing colloidal stability - the quantitative theory underlying colloidal stability being given by the extended Derjaguin-Landau and Verwey-Overbeek (DLVO) theory. Application of the extended DLVO theory to discrete colloidal particles in silicalite-1 precursor sols shows that a net repulsive interactive energy exists between the negatively charged particles. The thermal energy of the colloidal particles (1/2kT at 373 K, the crystallization temperature) is not sufficient to overcome the net repulsive energy barrier. The extended DLVO theory has been applied to two growth scenarios with similar results: growth by aggregation of particles of very different sizes and growth by aggregation of similar sized particles. The significance of these conclusions is that a proposed growth mechanism of MFI type zeolite (growth by aggregation of subcolloidal particles) is deemed not to be a reasonable description of molecular sieve growth. The conclusion that the colloidal crystals are stable with respect to aggregation is supported by experimental observations. The ideas presented in this study are based upon crystallization of molecular sieves from clear solutions in the presence of quaternary ammonium cations that play a significant role in the stabilization of the colloidal crystals. Extension of the ideas presented shows that the extended DLVO theory is equally applicable to wholly inorganic heterogeneous systems.
13.	Tosheva, Lubomira, et al. (författare) Silicalite-1 containing microspheres prepared using shape-directing macro-templates 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 35-36, s. 621-629 Tidskriftsartikel (refereegranskat)abstract Silicalite-1 microspheres were prepared by a novel method based on the use of anion exchange resins as shape-directing macro-templates. In a first step, spherical beads of the ion exchange resin were hydrothermally treated in a silicalite-1 synthesis solution. This resulted in the crystallization of silicalite-1 in the pores of the resin and the formation of a silicalite-1/resin composite material. The organic ion exchange resin was then removed by calcination leaving self-bonded spherical particles of silicalite-1. The influence of the type of ion exchange resin, the treatment time as well as the weight ratio between synthesis solution and resin on the properties of the resultant materials were investigated. The silicalite-1 containing microspheres were characterized by XRD, Raman spectroscopy, SEM, nitrogen adsorption and microhardness measurements.
14.	Tosheva, Lubomira, et al. (författare) Silicalite-1 macrostructures – preparation and structural features 2000 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 39:1-2, s. 91-101 Tidskriftsartikel (refereegranskat)abstract Zeolite macrostructures in the form of silicalite-1 spheres were prepared using anion exchange resin beads as shape directing macrotemplates. The resin was removed after the synthesis by combustion leaving solid spherical particles identical in shape and size to the original resin beads. The formation of the silicalite-1 spheres was studied by Raman spectroscopy, X-ray diffraction, scanning electron microscopy and nitrogen adsorption measurements. Samples prepared for different times of treatment and at two different temperatures, 100°C and 165°C, were investigated. The spheres obtained for short treatment times consist of amorphous silica, which after longer hydrothermal treatment in the presence of TPA cations is partially or entirely transformed into an MFI structure. A single treatment at 100°C resulted in hard silicalite-1 spheres of low crystallinity, whereas fully crystalline spheres could be obtained by a treatment at the higher temperature. However, the spheres prepared at 165°C have inferior mechanical properties and can even loose their shape at certain conditions. A better control of both hardness and crystallinity was achieved by using a two-step synthesis procedure, where a treatment at 100°C was followed by a treatment at 165°C.
15.	Tosheva, Lubomira, et al. (författare) Zeolite beta spheres 2001 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 48:1-3, s. 31-37 Tidskriftsartikel (refereegranskat)abstract Zeolite beta was crystallized from clear homogeneous solutions within the pores of anion exchange resin beads. The organic macrotemplate was then removed by combustion leaving stable macrospheres of zeolite beta. The zeolite beta crystallization within the resin beads was investigated by X-ray diffraction, Raman spectroscopy, SEM and nitrogen adsorption measurements. Crystallization within the macrotemplates was compared with the crystallization from bulk solution. The influence of the resin beads on the crystallization process was investigated by increasing the amount of ion exchanger present during synthesis and also by preparing bulk samples in the absence of macrotemplates.
16.	Wang, Zheng, et al. (författare) Synthesis of thin silicalite-1 films on steel supports using a seeding method 2002 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 52:3, s. 191-197 Tidskriftsartikel (refereegranskat)abstract Thin and continuous silicalite-1 films with controllable thickness between 200 and 800 nm were synthesized on steel supports by a method employing seeding. A variety of steel types ranging from ordinary carbon steel to highly corrosion resistant steel were used. Continuous transparent silicalite-1 films were formed on all steel types after zeolite synthesis. The type of steel did not affect the film morphology, the thickness or the preferred orientation of the crystals. The (5 0 1) reflection dominates in the XRD pattern for thin films whereas the (1 0 1) and (3 0 3) reflections dominate for thicker films. The silicalite-1 films on various stainless steel supports were stable during calcination, whereas a relatively thick magnetite/hematite film formed on carbon steel upon calcination and the silicalite-1 film detached.
17.	Abdel-Magied, Ahmed Fawzy, et al. (författare) Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements 2019 Ingår i: Microporous and Mesoporous Materials. - : Elsevier. - 1387-1811 .- 1873-3093. ; 278, s. 175-184 Tidskriftsartikel (refereegranskat)abstract Hierarchical porous zeolitic imidazolate frameworks nanoparticles (ZIF-8 NPs) were synthesized at room temperature via a template-free approach under dynamic conditions (stirring) using water as a solvent. The ZIF-8 NPs were evaluated as adsorbents for rare earth elements (La3+, Sm3+ and Dy3+). Adsorption equilibrium was reached after 7h and high adsorption capacities were obtained for dysprosium and samarium (430.4 and 281.1 mg g(-1), respectively) and moderate adsorption capacity for lanthanum (28.8 mg g(-1)) at a pH of 7.0. The high adsorption capacitiese, as well as the high stability of ZIF-8 NPs, make the hierarchical ZIF-8 materials as an efficient adsorbent for the recovery of La3+, Sm3+ and Dy3+ from aqueous solution.
18.	Abdelhamid, Hani Nasser, et al. (författare) Carbonized chitosan encapsulated hierarchical porous zeolitic imidazolate frameworks nanoparticles for gene delivery 2020 Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 302 Tidskriftsartikel (refereegranskat)abstract Hierarchical mesoporous carbon (MPC) nanomaterials derived from the carbonized chitosan (CTS) encapsulated zeolitic imidazolate frameworks (ZIF-8) is synthesized and applied for gene delivery. The synthesis of ZIF-8 is achieved at room temperature using water as a solvent in the presence of CTS within 60 min. The synthesis method offered a hierarchical porous structure of ZIF-8. The carbonization of the prepared materials leads to the formation of MPC nanomaterials. MPC materials were applied as a non-viral vectors for gene delivery using two oligonucleotides (ONs) called Luciferase-expressing plasmid (pGL3), and splice correction oligonucleotides (SCO). The materials are biocompatible and showed insignificant toxicity. The transfection using MPC with and without cell-penetrating peptides (CPPs) was reported. MPC improved the transfection efficiency of CPPs (PepFect 14 (PF-14), and PF-221) by 10 fold due to the synergistic effect of MCP and CPPs. The reasonable mechanism for the cell transfection using these new vectors was also highlighted.
19.	Abdelhamid, Hani Nasser, et al. (författare) Gene delivery using cell penetrating peptides-zeolitic imidazolate frameworks 2020 Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 300 Tidskriftsartikel (refereegranskat)abstract Cell-penetrating peptides (CPPs), and metal-organic frameworks (MOFs) are promising as next-generation for the delivery of gene-based therapeutic agents. Oligonucleotide (ON)-mediated assembly of nanostructures composed of hierarchical porous zeolitic imidazolate framework (ZIF-8), and nanoparticles such as graphene oxide (GO), and magnetic nanoparticles (MNPs) for gene therapy are reported. Five different types of non-viral vectors (ZIF-8, RhB@ZIF-8, BSA@ZIF-8, MNPs@ZIF-8, and GO@ZIF-8), and three gene therapeutic agents (plasmid, splice correction oligonucleotides (SCO), and small interfering RNA (siRNA)) were investigated. The polyplexes were characterized and applied for gene transfection. The materials show very low toxicity with high efficiency for luciferase transfection. ZIF-8 enhances the transfection of plasmid, SCO, siRNA of CPPs by 2-8 folds. The mechanism of the cell uptakes was also highlighted. Data reveal cell internalization via scavenger class A (SCARA).
20.	Abdelhamid, Hani Nasser, et al. (författare) Luminescence properties of a family of lanthanide metal-organic frameworks 2019 Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 279, s. 400-406 Tidskriftsartikel (refereegranskat)abstract Two isostructural series of lanthanide metal-organic frameworks denoted as SUMOF-7II (Ln) and SUMOF-7IIB (Ln) (Ln = La, Ce, Pr, Nd, Sm, Eu, and Gd) were synthesized using4,4',4 ''-(pyridine-2,4,6-triyl)tris(benzoic acid) (H(3)L2) and a mixture of H(3)L2 and 4,4',4 ''-(benzene-1,3,5-triyl)tris(benzoic acid) (H3BTB) as linkers, respectively. Both series were characterized using powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermal analysis (TGA), and photoluminescence spectroscopy. Photoluminescence measurements show that Eu-MOFs demonstrate a red emission while Pr- and Nd-MOFs display an emission in the near-infrared (NIR) range. On the other hand, La-, Ce-, Sm- and Gd-MOFs exhibit only a ligand-centered emission. The average luminescence lifetimes in the SUMOF-7IIB series are 1.3-1.4-fold longer than the corresponding ones in the SUMOF-7II series. SUMOF-7IIs show a good photo- and thermal stability. Altogether, the properties of SUMOF-7II and SUMOF-7IIB render them promising materials for applications including sensing, biosensing, and telecommunications.
21.	Aguilar, Wilson, et al. (författare) Dendritic growth of NBA-ZSM-5 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract Crystallization of ZSM-5 zeolite from a gel using n-butylamine as structure-directing agent was studied. Extreme high-resolution transmission and scanning electron microscopy showed the presence of dendritic features that are present at the crystal surface during most of the reaction time that become smoother towards completion of the crystallization. In addition, a web that likely stems from the gel, comprised of alumina-rich nanoparticles between the dendrites at the surface of the crystals was also identified. When the gel is not in direct contact with the crystal surface, dendrites and the web are not observed, and the crystals grow faster. Thus, the alumina-rich web retards the crystal growth and cause the formation of dendritic features.
22.	Al-Soubaihi, Rola, et al. (författare) Synthesis of hierarchically porous silica aerogel supported Palladium catalyst for low-temperature CO oxidation under ignition/extinction conditions 2020 Ingår i: Microporous and Mesoporous Materials. - : Elsevier. - 1387-1811 .- 1873-3093. ; 292 Tidskriftsartikel (refereegranskat)abstract Synthesis of well-dispersed palladium nanoparticles within silica aerogel pores with controlled size was carried out using sol-gel synthesis under supercritical ethanol drying. The high concentration of silanol groups on silica (SiO2) surface facilitated a superior palladium (Pd) loading up to 10 wt %. The synthesized Pd/SiO2 nanocomposite aerogels were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopic methods. The silica aerogel supported catalysts were found to have a wide pore size distribution. TEM investigations confirmed that Pd nanocrystals were located within the SiO2 microspores and mesopores. The catalyst was evaluated for carbon monoxide (CO) oxidation reaction under ignition/extinction conditions. The synthesized catalyst demonstrated a high catalytic activity at low operating temperatures (<200 °C) compared to unsupported Pd nanoparticles or bare SiO2 aerogels. This enhancement in CO oxidation activity with Pd/SiO2 aerogel catalysts are attributed to the small Pd particles, Pd interaction with the surface of the underlying SiO2 and the better dispersion of Pd particles within the SiO2 pores. Porosity played a more important role during the extinction cycle as a result of the slow dissipation of the heat leading to hysteresis. We demonstrate the influence of porosity of catalyst supports on the size, dispersion, and catalytic activity of Pd nanoparticles.
23.	Andersson, N, et al. (författare) Structural features and adsorption behaviour of mesoporous silica particles formed from droplets generated in a spraying chamber 2004 Ingår i: Microporous and Mesoporous Materials. - 1387-1811 .- 1873-3093. ; 72, s. 175-183 Tidskriftsartikel (refereegranskat)abstract Spherical mesoporous particles have been produced by spraying hydrolysed alkoxide solutions containing templating amphiphilic molecules. The modified spray drying method produces up to 10 g/h of spherical non-hollow particles with a size of 1–5 m. Transmission electron microscopy and X-ray diffraction showed that well ordered internal 2D hexagonal mesostructures could be prepared using both nonionic block copolymers and cationic surfactants as the templating molecules. Disordered cubic and well ordered lamellar, onion like, particles were prepared from the block copolymer templates. Nitrogen sorption data and mercury porosimetry show that pore size distribution of the mesoporous particles is very narrow with pore sizes varying from 2.5 to 8.5 nm as a function of templating amphiphiles. We have shown that the mesoscopic pores are accessible after calcination and can be filled with relatively large molecules; the particles adsorbed more than 20% (by weight) of the cationic dye Janus Green B from aqueous solutions.
24.	Asahina, Shunsuke, et al. (författare) A new HRSEM approach to observe fine structures of novel nanostructured materials 2011 Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 146:1-3, s. 11-17 Tidskriftsartikel (refereegranskat)abstract A new approach for observing fine structures of novel thin, nanostructured materials called through the employed to observe interesting features on a variety of new, catalyticallyimportant hierarchically porous rattlespheres.
25.	Atluri, Rambabu, et al. (författare) Structural variations in mesoporous materials with cubic Pm(3)over-barn symmetry 2010 Ingår i: Microporous and Mesoporous Materials. - : Elsevier BV. - 1387-1811 .- 1873-3093. ; 133:1-3, s. 27-35 Tidskriftsartikel (refereegranskat)abstract The fine structural details of mesoporous materials possessing Pmn symmetry prepared with varying amphiphilic surfactants under acid and alkaline conditions are investigated using electron crystallography and sorption studies. The structural data derived is used to understand the parameters that govern the formation of cavity–windows and to propose synthetic strategies in order to control independently the size of the cavities and cavity–windows. Results support that whilst attainment of Pmn cubic packing is due to the overall surfactant geometry, the formation of cavity–windows is associated with the hydration layer formed at the interphase between the surfactant and the silica wall. The charge density at the micelle surface may be tailored using two strategies: (i) using dicationic gemini surfactants at low pHs resulting in an increase in the hydration layer; or (ii) by using co-structure directing agents such as organoalkoxysilanes which reduce the hydration layer surrounding the micelles. The latter leads to the formation of higher cavity sizes and may be useful for tuning fine structural details of mesoporous materials when considering their use in important applications such as gas separation.

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