Preparation and Catalytic Activity of M2O3/CNTs (M = Y, Nd, Sm) Nanocomposites by Solvothermal Process

The rare-earth oxide nanoparticles along carbon nanotubes (CNTs) (M2O3/CNTs, M = Y, Nd, Sm) were prepared by in situ solvothermal method. Products were characterized by infrared spectroscopy, X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectrometry, scanning electron microscopy, and Brunauer-Emmett-Teller method. M2O3/CNTs presented good morphology and large surface area. Furthermore, catalysis of M2O3/CNTs during the thermal decomposition of ammonium perchlorate (AP) was evaluated by differential thermal analysis (DTA). Compared with Nd2O3/CNTs and Sm2O3/CNTs, Y2O3/CNTs nanocomposites showed the best catalytic effect on the thermal decomposition of AP. With the addition of 2 wt.% Y2O3/CNTs nanocomposite, high decomposition temperature of AP decreased by 125.5°C, and the total DTA heat release increased by 2.027 kJ·g−1.

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Combining In Situ Synchrotron X-Ray Diffraction and Absorption Techniques with Transmission Electron Microscopy to Study the Origin of Thermal Instability in Overcharged Cathode Materials for Lithium-Ion Batteries

Advanced Functional Materials ◽

10.1002/adfm.201200693 ◽

2012 ◽

Vol 23 (8) ◽

pp. 1047-1063 ◽

Cited By ~ 249

Author(s):

Kyung-Wan Nam ◽

Seong-Min Bak ◽

Enyuan Hu ◽

Xiqian Yu ◽

Youngning Zhou ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Lithium Ion Batteries ◽

Cathode Materials ◽

Thermal Instability ◽

Lithium Ion ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

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Late Mesozoic—Cenozoic clay mineral successions of southern Iran and their palaeoclimatic implications

Clay Minerals ◽

10.1180/0009855054020165 ◽

2005 ◽

Vol 40 (2) ◽

pp. 191-203 ◽

Cited By ~ 15

Author(s):

F. Khormali ◽

A. Abtahi ◽

H. R. Owliaie

Keyword(s):

Electron Microscopy ◽

Upper Cretaceous ◽

Sedimentary Rocks ◽

X Ray Diffraction ◽

Humid Climate ◽

X Ray ◽

Late Mesozoic ◽

Southern Iran ◽

Transmission Electron

AbstractClay minerals of calcareous sedimentary rocks of southern Iran, part of the old Tethys area, were investigated in order to determine their origin and distribution, and to reconstruct the palaeoclimate of the area. Chemical analysis, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and thin-section studies were performed on the 16 major sedimentary rocks of the Fars and Kuhgiluyeh Boyerahmad Provinces.Kaolinite, smectite, chlorite, illite, palygorskite and illite-smectite interstratified minerals were detected in the rocks studied. The results revealed that detrital input is possibly the main source of kaolinite, smectite, chlorite and illite, whilein situneoformation during the Tertiary shallow saline and alkaline environment could be the dominant cause of palygorskite occurrences in the sedimentary rocks.The presence of a large amount of kaolinite in the Lower Cretaceous sediments and the absence or rare occurrence of chlorite, smectite, palygorskite and illite are in accordance with the warm and humid climate of that period. Smaller amounts of kaolinite and the occurrence of smectite in Upper Cretaceous sediments indicate the gradual shift from warm and humid to more seasonal climate. The occurrence of palygorskite and smectite and the disappearance of kaolinite in the late Palaeocene sediments indicate the increase in aridity which has probably continued to the present time.

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In Situ Study of the Reaction Sequence in the Sol–Gel Synthesis of a (Ba0.5Sr0.5)(Co0.8Fe0.2)O3−δPerovskite by X-Ray Diffraction and Transmission Electron Microscopy

Journal of the American Ceramic Society ◽

10.1111/j.1551-2916.2007.01932.x ◽

2007 ◽

Vol 90 (11) ◽

pp. 3651-3655 ◽

Cited By ~ 16

Author(s):

Mirko Arnold ◽

Haihui Wang ◽

Julia Martynczuk ◽

Armin Feldhoff

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Sol Gel ◽

X Ray Diffraction ◽

Reaction Sequence ◽

X Ray ◽

In Situ Study ◽

Transmission Electron ◽

Sol Gel Synthesis

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Size dependent behavior of Fe3O4crystals during electrochemical (de)lithiation: an in situ X-ray diffraction, ex situ X-ray absorption spectroscopy, transmission electron microscopy and theoretical investigation

Physical Chemistry Chemical Physics ◽

10.1039/c7cp03312e ◽

2017 ◽

Vol 19 (31) ◽

pp. 20867-20880 ◽

Cited By ~ 27

Author(s):

David C. Bock ◽

Christopher J. Pelliccione ◽

Wei Zhang ◽

Janis Timoshenko ◽

K. W. Knehr ◽

...

Keyword(s):

Electron Microscopy ◽

Structural Changes ◽

Ex Situ ◽

X Ray Diffraction ◽

X Ray ◽

Size Dependent ◽

Transmission Electron ◽

Dependent Behavior ◽

X Ray Absorption

Crystal and atomic structural changes of Fe3O4upon electrochemical (de)lithiation were determined.

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Magnetic Pd/Fe3O4 Composite: Synthesis, Structure, and Catalytic Activity

Australian Journal of Chemistry ◽

10.1071/ch14148 ◽

2014 ◽

Vol 67 (10) ◽

pp. 1387 ◽

Cited By ~ 3

Author(s):

Shi-Qiang Bai ◽

Lu Jiang ◽

Sheng-Li Huang ◽

Ming Lin ◽

Shuang-Yuan Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Catalytic Activity ◽

Reduction Process ◽

Pd Nanoparticles ◽

Pincer Ligands ◽

X Ray Diffraction ◽

X Ray ◽

Good Thermal Stability ◽

Transmission Electron

Composite Pd/Fe3O4 (1) was designed and synthesised by immobilization of tridentate pincer ligands with triethoxysilane groups on Fe3O4 nanoparticles, PdII complexation, and in-situ reduction process. The composite was characterised by transmission electron microscopy, scanning electron microscopy energy-dispersive X-ray spectroscopy, powder X-ray diffraction, vibrating sample magnetometer, Fourier transform infrared spectroscopy, thermogravimetric analysis, and Brunauer–Emmett–Teller analysis. The composite featured Pd nanoparticles of ~2–4 nm, exhibited good thermal stability and hydrophilic property as well as excellent catalytic activity towards the reduction of 4-nitrophenol to 4-aminophenol in water.

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Morphology of Polyethylene/Montmorillonite Nanocomposites Prepared by In Situ Polymerization

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.457-458.244 ◽

2013 ◽

Vol 457-458 ◽

pp. 244-247

Author(s):

Min Li ◽

Li Guang Xiao ◽

Hong Kai Zhao

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

In Situ Polymerization ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Reflection Peak ◽

Basal Reflection ◽

Scanning Electron

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The morphology of MMT/MgCl2/TiCl4 catalyst and PE/MMT nanocomposites was investigated by scanning electron microscopy (SEM). It can be seen that MMT/MgCl2/TiCl4 catalyst remained the original MMT sheet structures and many holes were found in MMT and the morphology of PE/MMT nanocomposites is part of the sheet in the form of existence, as most of the petal structure. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were carried out to characterize all the samples. XRD results reveal that the original basal reflection peak of PEI1 and PEI2 disappears completely and that of PEI3 become very weak. MMT/MgCl2/TiCl4 catalyst was finely dispersed in the PE matrix. Instead of being individually dispersed, most layers were found in thin stacks comprising several swollen layers.

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In situ x-ray study of the γ- to α-Al2O3 phase transformation during atmospheric pressure oxidation of NiAl(110)

Journal of Materials Research ◽

10.1557/jmr.2006.0397 ◽

2006 ◽

Vol 21 (12) ◽

pp. 3047-3057 ◽

Cited By ~ 11

Author(s):

A. Vlad ◽

A. Stierle ◽

N. Kasper ◽

H. Dosch ◽

M. Rühle

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Orientation Relationship ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Oxidation In Air ◽

Α Al2o3 ◽

Underlying Substrate

The oxidation in air of NiAl(110) was investigated in the temperature range from 870 °C–1200 °C by in situ x-ray diffraction and transmission electron microscopy. Oxidation at 870 °C and 1 bar oxygen leads to the formation of an epitaxial layer of γ-alumina showing an R30° orientation relationship with respect to the underlying substrate. At oxidation temperatures between 950 °C and 1025 °C, we observed a coexistence of epitaxial γ- and polycrystalline δ-Al2O3. The α-Al2O3 starts to form at 1025 °C and the complete transformation of metastable phases to the stable α-alumina phase takes place at 1100 °C. The fcc-hcp martensitic-like transformation of the initial γ-Al2O3 to epitaxial α-Al2O3 was observed. X-ray diffraction and cross-section transmission electron microscopy proved the existence of a continuous epitaxial α-Al2O3 layer between the substrate and the polycrystalline oxide scale, having a thickness of about 150 nm. The relative orientation relationship between the epitaxial alumina and the underlying substrate was found to be NiAl(110) || α-Al2O3 (0001) and [110] NiAl || [1120].

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Preparation, characterization, and properties of polystyrene/Na-montmorillonite composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718785691 ◽

2018 ◽

Vol 32 (8) ◽

pp. 1078-1091 ◽

Cited By ~ 4

Author(s):

Sibel Erol Dağ ◽

Pınar Acar Bozkurt ◽

Fatma Eroğlu ◽

Meltem Çelik

Keyword(s):

Electron Microscopy ◽

Interlayer Spacing ◽

Decomposition Temperature ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Sem Images ◽

Specific Pore Volume ◽

Transmission Electron ◽

Thermal Stability Of

A series of polystyrene (PS)/unmodified Na-montmorillonite (Na-MMT) composites were prepared via in situ radical polymerization. The prepared composites were characterized using various techniques. The presence of various functional groups in the unmodified Na-MMT and PS/unmodified Na-MMT composite was confirmed by Fourier transform infrared spectroscopy. Morphology and particle size of prepared composites was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to the XRD and TEM results, the interlayer spacing of MMT layers was expanded. SEM images showed a spongy and porous-shaped morphology of composites. TEM revealed the Na-MMT intercalated in PS matrix. The thermal stability of PS/unmodified Na-MMT composites was significantly improved as compared to PS, which is confirmed using thermogravimetric analysis (TGA). The TGA curves indicated that the decomposition temperature of composites is higher at 24–51°C depending on the composition of the mixture than that of pure PS. The differential scanning calorimetry (DSC) results showed that the glass transition temperature of composites was higher as compared to PS. The moisture retention, water uptake, Brunauer–Emmett–Teller specific surface area, and specific pore volume of composites were also investigated. Water resistance of the composites can be greatly improved.

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