Dispersion of TiO2 Nanotubes in a Chitosan Matrix

ABSTRACTThis work presents the synthesis and characterization of TiO2 nanotubes (NTT) with chitosan (CS). In a first stage, electrochemical anodization of titanium foils was used to generate NTT in a membrane-type arrangement. From these experiments, suitable experimental conditions were selected. In a second stage, the synthesized NTT were detached from the titanium foils by sonication. In the third stage, the detached NTT were dispersed in an acid solution containing CS in various concentrations. Finally, the nanotubes-chitosan (NTT/CS) samples were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectrometry (FTIR). Our results showed that the NTT presented very regular tube morphology with -OH and Ti-O- functional groups on the surface. The interaction of NTT and chitosan was enhanced by increasing the time of contact during the synthesis of the titanium composites.

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Preparation and Characterization of a Novel Flame Retardant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.294 ◽

2008 ◽

Vol 47-50 ◽

pp. 294-297 ◽

Cited By ~ 1

Author(s):

Xiu Wei Jia ◽

Min Zhi Rong ◽

Ming Qiu Zhang

Keyword(s):

Flame Retardant ◽

Sol Gel ◽

Average Molecular Weight ◽

Regular Structure ◽

Gel Permeation Chromatography ◽

Helical Conformation ◽

Infrared Spectrometry ◽

Resonance Spectroscopy ◽

X Ray Diffraction

A novel flame retardant polymethylsilsesquioxane (PMSQ) was successfully obtained via combination of non-hydrolytic and hydrolytic sol-gel routes. Chemical structure of the resultant PMSQ was determined by nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectrometry and powder X-ray diffraction, respectively. All the measurements demonstrated that the product possessed regular structure with chain-to-chain width of 0.87nm and chain thickness of 0.40nm. Weight average molecular weight of PMSQ was measured to be 3.5×105 using gel permeation chromatography. Numerical simulations of the molecular structure suggested that PMSQ should exhibit cis-isotactic configuration and double helical conformation at undisturbed condition.

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Low-Cost Synthesis of Cu-Modified Immobilized Nanoporous TiO2 for Photocatalytic Degradation of 1H-Benzotriazole

Catalysts ◽

10.3390/catal10010019 ◽

2019 ◽

Vol 10 (1) ◽

pp. 19 ◽

Cited By ~ 3

Author(s):

Tihana Čižmar ◽

Ivana Panžić ◽

Krešimir Salamon ◽

Ivana Grčić ◽

Lucija Radetić ◽

...

Keyword(s):

Photocatalytic Activity ◽

Spin Coating ◽

Low Cost ◽

Electrochemical Anodization ◽

Synthesis Methods ◽

X Ray Diffraction ◽

X Ray ◽

Surface Areas ◽

Titanium Foils ◽

The Given

Cu-modified immobilized nanoporous TiO2 photocatalysts, prepared by electrochemical anodization of titanium foils, were obtained via four different synthesis methods: hydrothermal synthesis, anodization with Cu source, electrodeposition, and spin-coating, using two different copper sources, Cu(NO3)2 and Cu(acac)2. The objective of this research was to investigate how copper modifications can improve the photocatalytic activity of immobilized nanoporous TiO2 under the UV/solar light irradiation. The best photocatalytic performances were obtained for Cu-modifications using spin-coating. Therefore, the effect of irradiated catalyst surface areas on the adsorption of model pollutants, methylene blue (MB) and 1H-benzotriazole (BT), was examined for samples with Cu-modification by the spin-coating technique. The mechanisms responsible for increased degradation of MB and BT at high Cu concentrations (0.25 M and 0.5 M) and decreased degradation at low Cu loadings (0.0625 M and 0.125 M) were explained. 1H-benzotriazole was used to study the photocatalytic activity of the given samples because it is highly toxic and present in most water systems. The characterization of the synthesized Cu-modified photocatalysts in terms of phase composition, crystal structure, and morphology were investigated using X-ray Diffraction, Raman Spectroscopy, Scanning Electron Microscopy, and Energy Dispersive X-ray spectroscopy.

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Microstructural Characterization of Multiphase Coatings Produced By Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-168-159 ◽

1989 ◽

Vol 168 ◽

Cited By ~ 5

Author(s):

R. A. Lowden ◽

K. L. More ◽

T. M. Besmann ◽

R. D. James

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Analytical Electron Microscopy ◽

Chemical Vapor ◽

Microstructural Characterization ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Analytical Electron ◽

Scanning Transmission

AbstractChemical vapor deposition has been utilized to produce ternary, multiphase coatings of various compositions of silicon carbide (SiC) with Ti, Cr, and Mo. Thermodynamic calculations have been performed for a variety of experimental conditions in each system. Scanning, transmission and analytical electron microscopy, and X-ray diffraction techniques have been used to characterize the microstructures and to determine compositions.

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Hydrothermal Synthesis and Characterization of Single-Crystalline -Fe2O3Nanocubes

Journal of Nanomaterials ◽

10.1155/2011/159259 ◽

2011 ◽

Vol 2011 ◽

pp. 1-5 ◽

Cited By ~ 26

Author(s):

Wenqing Qin ◽

Congren Yang ◽

Ran Yi ◽

Guanhua Gao

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Infrared Spectrometry ◽

X Ray Diffraction ◽

Single Crystalline ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Alkaline Agent ◽

One Step

Single-crystalline - nanocubes were successfully obtained in large quantities through a facile one-step hydrothermal synthetic route under mild conditions. In this synthetic system, aqueous iron (III) nitrate () served as iron source and triethylamine served as precipitant and alkaline agent. By prolonging reaction time from 1 h to 24 h, the evolution process of -, from nanorhombohedra to nanohexahedron, and finally nanocube, was observed. The products were characterized by Powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), High-resolution Transmission Electron Microscopy (HRTEM), Selected-Area Electron Diffraction (SAED), and Fourier Transform Infrared Spectrometry (FTIR). The possible formation mechanism was discussed on basis of the experimental results.

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Preparation and Characterization of NiO Nanoparticles through Thermal Decomposition of Bis(glycinato)Nickel(II)dihydrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.601.21 ◽

2012 ◽

Vol 601 ◽

pp. 21-25

Author(s):

Wei Yi Dan ◽

Jian Fen Li ◽

Xiang Chen Tu ◽

Kui Le Jia

Keyword(s):

Reaction Time ◽

Fourier Transforms ◽

Infrared Spectrometry ◽

Nio Nanoparticles ◽

X Ray Diffraction ◽

Fine Crystal ◽

Transmission Electron ◽

Mean Size ◽

Ft Ir

NiO nanoparticles were successfully prepared by decomposing the predecessor bis(glycinato)nickel(II)dihydrate in the presence of oleylamine and triphenylphosphine (TPP), and different approaches including Fourier transforms infrared spectrometry(FT-IR), X-ray diffraction(XRD) and transmission electron microscopy (TEM) were used to characterize the NiO nanoparticles. Meanwhile, the effects of TPP concentration and reaction time on the size and yield of NiO nanoparticles derived from precursors were thoroughly investigated in this paper. The analysis results indicated that the prepared NiO nanoparticles were found spherical in shape and demonstrated weak agglomeration. They had generally high purity and a fine crystal phase of cubic syngony. Furthermore, the effects of the TPP concentration and reaction time on the size and yield of NiO nanoparticles are very crucial, higher concentration of TPP would results in reduction of both the mean size and yield of NiO particles. However both yields and particles size of NiO nanoparticles continuously increased as increasing reaction time, after more than 60 minutes, the size and yield of NiO nanoparticles kept hardly change.

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Physical and Structural Characterization of Monocrystalline Cu-13.7% Al-4.2% Ni Alloy Submitted to Thermo-Cyclical Treatments under Applied Loads

Metals ◽

10.3390/met10020219 ◽

2020 ◽

Vol 10 (2) ◽

pp. 219

Author(s):

Lioudmila A. Matlakhova ◽

Elaine C. Pereira ◽

Serguey A. Pulnev ◽

Carlos Y. Shigue ◽

Natalia A. Palii

Keyword(s):

Martensitic Transformations ◽

Nominal Composition ◽

Special Device ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Optimum Load ◽

Ni Alloy ◽

Complex Structural ◽

Martensite Reorientation

Monocrystalline alloy with a nominal composition of Cu-13.7% Al-4.2% Ni (wt.%) that shows reversible martensitic transformations (RMTs) was studied. The alloy, manufactured by the “Memory Crystals Group” in Russia, was subjected to thermo-cyclical treatment (TCT) under tension within a range that included critical RMT temperatures. A special device was developed to perform TCTs (up to 500 cycles) and three different loads were applied: 0.11, 0.26, and 0.53 MPa. X-ray diffraction analysis, optical microscopy, differential calorimetry, and Vickers microhardness were involved in the alloy’s characterization. Under TCTs, the alloy displayed complex structural transformation, revealing the sequence of RMT, β1 ↔ R ↔ β′1 + γ′1; the involved phases were coherently precipitated but very sensitive to the experimental conditions. It was found that during TCTs (from 300 cycles) performed under optimum load (0.26 MPa), the processes of martensite reorientation, hardening, and stabilization of the structure were the most intensive thus leading to a reduction of RMT critical intervals and increased microhardness.

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Fracture Characterization of High Density Polyethylene/Organoclay Nanocomposites Toughened with SEBS-g-MA

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.312.187 ◽

2006 ◽

Vol 312 ◽

pp. 187-192 ◽

Cited By ~ 1

Author(s):

S.P. Bao ◽

Sie Chin Tjong

Keyword(s):

Fracture Toughness ◽

High Density Polyethylene ◽

High Density ◽

Infrared Spectrometry ◽

X Ray Diffraction ◽

Fracture Characterization ◽

X Ray ◽

Melt Compounding ◽

Work Of Fracture

High density polyethylene (HDPE)/organoclay nanocomposites toughened with maleated styrene-ethylene-butylene-styrene elastomer (SEBS-g-MA) were prepared by melt compounding. The structure and mechanical properties of such nanocomposites were investigated by X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), tensile and impact techiniques. XRD measurements showed that meleic anhydride group of SEBS elastomer was beneficial in forming an intercalated or partially exfoliated structure. The essential work of fracture (EWF) approach under tensile condition was used to characterize the fracture toughness of nanocomposites. The results indicated that the addition of SEBS-g-MA to the HDPE/organoclay nanocomposites greatly enhanced their fracture toughness.

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Small-angle scattering for beginners

Journal of Applied Crystallography ◽

10.1107/s1600576721010293 ◽

2021 ◽

Vol 54 (6) ◽

Author(s):

Cedric J. Gommes ◽

Sebastian Jaksch ◽

Henrich Frielinghaus

Keyword(s):

Small Angle ◽

Small Angle Scattering ◽

X Rays ◽

X Ray Diffraction ◽

Experimental Conditions ◽

Time Resolved ◽

Characterization Methods ◽

Angle Scattering

Many experimental methods are available for the characterization of nanostructures, but most of them are limited by stringent experimental conditions. When it comes to analysing nanostructures in the bulk or in their natural environment – even as ordinary as water at room temperature – small-angle scattering (SAS) of X-rays or neutrons is often the only option. The rapid worldwide development of synchrotron and neutron facilities over recent decades has opened unprecedented possibilities for using SAS in situ and in a time-resolved way. But, in spite of its huge potential in the field of nanomaterials in general, SAS is covered far less than other characterization methods in non-specialized curricula. Presented here is a rigorous discussion of small-angle scattering, at a technical level comparable to the classical undergraduate coverage of X-ray diffraction by crystals and which contains diffraction as a particular case.

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Synthesis and characterization of montmorillonite clays with modulable porosity induced with acids and superacids

Journal of Materials Research ◽

10.1557/jmr.2007.0098 ◽

2007 ◽

Vol 22 (3) ◽

pp. 788-800 ◽

Cited By ~ 12

Author(s):

Y. Marina Vargas Rodríguez ◽

Hiram I. Beltrán ◽

Eloy Vázquez-Labastida ◽

Carlos Linares-López ◽

Manuel Salmón

Keyword(s):

Lamellar Structure ◽

Capillary Condensation ◽

Infrared Spectrometry ◽

X Ray Diffraction ◽

Full Characterization ◽

Surface Areas ◽

Partial Digestion ◽

Montmorillonite Clays ◽

Complete Digestion

The structural transformation of natural montmorillonite clay with different acids and superacids (hydrochloric, HCl; sulfuric, H2SO4; hydrofluoric, HF; perchloric, HClO4; chlorosulfonic, HSO3Cl; and trifluoromethanesulfonic, HSO3CF3 acids) is evaluated by various techniques, allowing its full characterization. The process involves the modulated digestion of the aluminum and silicon atoms from the original clay without the loss of the original mass in the material from a careful drying methodology. The x-ray diffraction technique suggests that the process is disruptive, causing different magnitudes of modification, depending on the acidic source, taking the material with natural lamellar structure as reference. By 27Al and 29Si magnetic resonance, it is also shown that all the silicon and aluminum atoms were removed from the chemical structure to be physisorbed or dispersed in the interstices of the clay lattice when HF, HSO3Cl, and H2SO4 acid treatments were carried out. However, with treatment of HClO4, the results suggest that only was achieved partial digestion and physisorption of the aluminosilicate core. Treatment with HCl led to a mild digestion that increased the laminar distance of the montmorillonite. Finally, HSO3CF3 acid achieved a total disorder of the lamellar structure of the clay. In addition, by infrared spectrometry, the disappearance of the absorption peaks assigned to Al2OH, AlMgOH, and Al-O-Si are other evidence of the complete digestion of silicon and aluminum atoms caused by the acidic medium. On the other hand, the Brunauer–Emmett–Teller (BET) surface areas of the acidified clays showed a great enlargement in comparison with the unmodified clay. The porosimetry measurements demonstrate the presence of mesopores and hysteresis as observed in the physisorption isotherms, which indeed exhibited a capillary condensation into the porous structures. The present results are the first full characterization research and structural comparison between the acidic and the not-extensively-studied superacidic modified clays of this type.

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Synthesis and Characterization of Topological Insulator Bi2Te3 Nanowires

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.645-646.32 ◽

2015 ◽

Vol 645-646 ◽

pp. 32-39

Author(s):

Zhen Guo ◽

Lan Lu ◽

Jing Yun Wang ◽

Ying Jie Xing

Keyword(s):

Low Cost ◽

Diffraction Field ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Facile Hydrothermal Method ◽

Experimental Conditions ◽

X Ray ◽

Structure And Morphology ◽

Transmission Electron

Bi2Te3 nanowires are prepared by a low-cost and facile hydrothermal method without any surfactant. The structure and morphology of the nanowires are characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscope. The influences of experimental conditions on the products are investigated. The growth mechanism is proposed based on the experimental results. This work is promising for the synthesis of Bi2Te3 nanowires with less impurity.

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