Characteristic and Preparation of TiO2/PVP Nanofiber Using Electrospinning Technique

2019 ◽  
Vol 798 ◽  
pp. 223-228
Author(s):  
Tawat Soitong ◽  
Supattra Wongsaenmai
Keyword(s):  
Calcination Temperature ◽  
Composite Nanofibers ◽  
Structural Phase ◽  
Homogeneous Solution ◽  
Titanium Isopropoxide ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Chemical Structures ◽  
Thermal Analyzer ◽  
Microscope Technique

In this work, titanium dioxide (TiO2) ceramic nanofiber was prepared by homemade electrospinning technique. A homogeneous solution of titanium isopropoxide in polyvinyl pyrrolidone (PVP) was prepared. The thermal behavior of the fiber was characterized by differential thermal analyzer (DTA) and thermogravimetric analysis (TGA) to obtain the calcination temperature range. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the chemical structures of the TiO2/PVP composite nanofibers. The structural phase formations were characterized by x-ray diffraction technique (XRD). It has been found that the single phase of anatase and rutile were obtained at the calcinations temperature at 500 and 900 °C, respectively. The microstructure was characterized by a scanning electron microscope technique (SEM). The diameter of titanium oxide nanofibers were in the range of 70 nm to 300 nm and decrease as the calcination temperature increasing. The results indicated the effect of calcination temperature on the crystalline phase and morphology of the nanofiber.

Fabrication of Li0.06(K0.5,Na0.5)0.94NbO3 Nanofibers by Electrospinning Technique

2019 ◽  
Vol 798 ◽  
pp. 218-222
Author(s):  
Supattra Wongsaenmai ◽  
Tawat Soitong
Keyword(s):  
Calcination Temperature ◽  
Single Phase ◽  
Sol Gel ◽  
Structural Phase ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Fiber Morphology ◽  
Electrospinning Technique ◽  
X Ray ◽  
Sol Gel Process

In this work, Li0.06(K0.5,Na0.5)0.94NbO3(KNNL) nanofibers were synthesized by sol–gel process and electrospinning technique. The thermal behaviour ofelectrospun fibers was characterized by thermogravimetric analysis (TG) to obtain the calcination temperature range. The structural phase formation and microstructure were characterized by X-ray diffraction technique (XRD) and scanning electron microscopy (SEM), respectively. The crystal structure was identified by XRD as a single-phase perovskite structure, with orthorhombic symmetry. The microstructure shows that the diameters are in the range of 80–160 nm. The electrospun fibers were calcined from 500°C to 900°C and observed the fiber morphology. With increasing calcination temperature, the fiber diameters decreased until the temperature up to 900 °C the morphology change from cylinder to square or rectangular shape grains.

Preparation and Characterization of Porous Carbon/Nickle Nanofibers by Electrospinning

2013 ◽  
Vol 853 ◽  
pp. 101-104
Author(s):  
Da Wei Gao ◽  
Qu Fu Wei ◽  
Chun Xia Wang ◽  
Guo Liang Liu ◽  
Xue Mei He ◽  
...  
Keyword(s):  
Carbon Nanofibers ◽  
Porous Carbon ◽  
Composite Nanofibers ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Bet Analysis ◽  
The Face ◽  
Fibrous Morphology ◽  
Face Centered

By employing the electrospinning technique and subsequent carbonization processes, porous carbon/nickle (C/Ni) composite nanofibers with diameters of 100-200 nm were successfully prepared. Two polymer solutions of polyacrylonitrile (PAN), polyvinyl pyrrolidone (PVP), and Ni (CH3COOH)2(Ni (OAc)2) were used as C/Ni composite nanofiber precursors. The study revealed that C/Ni composite nanofibers were successfully prepared and nickle particles with diameters of 20-70 nm were uniformly scattered in the carbon nanofibers. It was also observed that the fiber with clear fibrous morphology with particles broke into shorter fibers after sinter. X-ray diffraction (XRD) showed that these particles crystallized with the face centered cubic (FCC) structure. The Brunauer-Emmett-Teller (BET) analysis indicated that C/Ni composites nanofibers with meso-pores possessed larger specific surface area than that of carbon nanofibers.

Preparation and Application of Supramolecular Assembled β-cyclodextrin/polyacrylonitrile Composite Nanofibers as a Highly Efficient Adsorbent for Dye Removal

2012 ◽  
Vol 622-623 ◽  
pp. 827-832 ◽  
Author(s):  
Arvind H. Jadhav ◽  
Hern Kim
Keyword(s):  
Adsorption Capacity ◽  
Composite Nanofibers ◽  
Dye Removal ◽  
Methyl Violet ◽  
Homogeneous Solution ◽  
Ftir Analysis ◽  
Experimental Conditions ◽  
Electrospinning Technique ◽  
Adsorption Performance ◽  
Efficient Adsorbent

β-cyclodextrin (β-CD) incorporated polyacrylonitrile (PAN) composite nanofibers were successfully prepared by using electrospinning technique and used as a novel adsorbent for the elimination of dyes from aqueous solution. The formations of bead-free and uniform nanofibers were obtained using various compositions of homogeneous solution of β-CD and PAN in N,N-dimethylformamide (DMF). The morphology and structure of nanofibers were determined and characterized by SEM, XRD, TGA, and FTIR analysis. The adsorption performance of prepared nanofibers was examined by using methylene blue (MB) and methyl violet (MV) as adsorbate. Results showed that β-CD/PAN nanofibers were achieved equilibrium point within 2h with 96.21 % and 94.37 % adsorption of MV and MB, respectively at ambient condition. In addition, adsorption capacity of nanofibers was studied under different experimental conditions and their effects on adsorption capacity such as temperature, pH, and contact time. The regeneration of β-CD/PAN nanofibers were carried out using methanol and re used five times as an adsorbent, Results indicates that regenerated adsorbent was adsorb 89.0% and 85.22 % of MV and MB, respectively in 5th cycle.

Structural Properties Dependence on Annealing Temperature of 1-D Lanthanum Iron Garnet Nanofiber Prepared via Electrospinning Technique

2019 ◽  
Vol 59 ◽  
pp. 105-111
Author(s):  
Mohamad Ashry Jusoh ◽  
Fahmiruddin Esa ◽  
Rodziah Nazlan
Keyword(s):  
Calcination Temperature ◽  
Structural Properties ◽  
Annealing Temperature ◽  
Structure Change ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Calcination Process ◽  
X Ray ◽  
Continuous Structure ◽  
Iron Garnet

The effect of anealing temperature on structural properties of Lanthanum Iron Garnet (LIG) nanofiber has been studied. The LIG nanofiber were prepared by electrospinning technique. This technique has been extensively developed as a simple and efficient method for drawing nanofibers from polymer solutions. The viscous LIG solution were loaded in syringe and were pumped at 0.05 mL/h. The nanofibers were collected on aluminium foil and were treated at 700 °C, 750 °C and 1000 °C in order to study the effect of annealing temperature to the nanofibers structure. X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM) were employed to study the phase formation and morphology of the samples. The XRD results of LIG nanofiber reveals that as the annealing temperature increases from 700 °C to 1000 °C, the corresponding peaks become sharper and narrower, which demonstrate the improvement of crystallinity and crystallite size. The FESEM images of LIG nanofiber demonstrates that the nanofibers treated at 700 °C have continuous structure with a relatively rough surface and their diameter range is within 41.3 nm and 58.7 nm. Subsequently, when the calcination temperature increase further, the morphology of the sample is dramatically changed. As calcinations temperature rises to 750 °C, the surface of resultant nanofibers start to become agglomerate due to the growth and coalescence of the particle in the nanofibers under the calcination process and the nanofibers structure change back to continuous structure with bigger diameter at 1000 °C as compared to calcination temperature of 700 °C.

Synthesis, Characterization of Electrospun Mesoporous ZnO/SnO2 Composites Nanofibers and their Photocatalytic Property

2012 ◽  
Vol 463-464 ◽  
pp. 548-554
Author(s):  
Rui Lai Liu ◽  
Pei Zheng Chen ◽  
Jun Shao Liu ◽  
Hui Hua Jiang ◽  
Liang Bi Chen
Keyword(s):  
Electron Microscopy ◽  
Composite Nanofibers ◽  
Coupling Effect ◽  
Photocatalytic Property ◽  
Pure Sno2 ◽  
X Ray Diffraction ◽  
Electrospinning Technique ◽  
Electron Pairs ◽  
Transmission Electron ◽  
Mesoporous Zno

Mesoporous ZnO/SnO2 (Zn : Sn = 2 : 1) composite nanofibers with diameter of 49±6 nm and pore size of 6.7 nm were fabricated via the electrospinning technique. Their structure and morphology were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV–vis diffuse reflectance spectra (DRS) and nitrogen absorption-desorption isotherm analysis. The photocatalytic degradation rate of RhB dye by the mesoporous ZnO/SnO2 composite nanofibers was 0.051 min-1, which was more than two times and seven times of that by the pure ZnO (0.024 min-1) and pure SnO2 (0.007 min-1) nanofibers, respectively. The charge separation of electrons and holes was promoted and the recombination of the hole-electron pairs was reduced because of the coupling effect of ZnO and SnO2 in the grain-like composite nanoparticles, thus the quantum efficiency was increased. A schematic diagram of photocatalytic mechanism of mesoporous ZnO/SnO2 composite nanofibers was presented.

Highly thermally conductive UHMWPE/NG composites with the segregated structure and their application for heat spreader

2020 ◽  
pp. 089270572096564
Author(s):  
Xiao Wang ◽  
Hui Lu ◽  
Jun Chen
Keyword(s):  
Thermal Conductivity ◽  
Laser Flash ◽  
Heating Process ◽  
X Ray Diffraction ◽  
Heat Spreader ◽  
Conductive Composites ◽  
Compression Direction ◽  
Thermal Analyzer ◽  
Thermally Conductive ◽  
Plane Direction

In this work, ultra-high molecular weight polyethylene (UHMWPE)/natural flake graphite (NG) polymer composites with the extraordinary high thermal conductivity were prepared by a facile mixed-heating powder method. Morphology observation and X-ray diffraction (XRD) tests revealed that the NG flakes could be more tightly coated on the surface of UHMWPE granules by mixed-heating process and align horizontally (perpendicular to the hot compression direction of composites). Laser flash thermal analyzer (LFA) demonstrated that the thermal conductivity (TC) of composites with 21.6 vol% of NG reached 19.87 W/(m·K) and 10.67 W/(m·K) in the in-plane and through-plane direction, respectively. Application experiment further demonstrated that UHMWPE/NG composites had strong capability to dissipate the heat as heat spreader. The obtained results provided a valuable basis for fabricating high thermal conductive composites which can act as advanced thermal management materials.

scholarly journals New Haloterpenes from the Marine Red Alga Laurencia papillosa: Structure Elucidation and Biological Activity

Marine Drugs ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 35
Author(s):  
Mohamed Shaaban ◽  
Ghada S. E. Abou-El-Wafa ◽  
Christopher Golz ◽  
Hartmut Laatsch
Keyword(s):  
Biological Activity ◽  
Crude Extract ◽  
Structure Elucidation ◽  
Antimicrobial Activities ◽  
Red Alga ◽  
Spectroscopic Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Structures ◽  
Terpene Derivatives

Analysis of the air-dried marine red alga Laurencia papillosa, collected near Ras-Bakr at the Suez gulf (Red Sea) in Egypt delivered five new halogenated terpene derivatives: aplysiolic acid (1), 7-acetyl-aplysiol (2), aplysiol-7-one (3), 11,14-dihydroaplysia-5,11,14,15-tetrol (5a), and a new maneonene derivative 6, named 5-epi-maneolactone. The chemical structures of these metabolites were characterized employing spectroscopic methods, and the relative and absolute configurations were determined by comparison of experimental and ab initio-calculated NMR, NOE, ECD, and ORD data, and by X-ray diffraction of 2 and 6. The antimicrobial activities of the crude extract and compounds 1–3, 5a and 6 were studied.

scholarly journals Synthesis and Characterization of N-Substituted Polyether-Block-Amide Copolymers

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 773
Author(s):  
Jyun-Yan Ye ◽  
Kuo-Fu Peng ◽  
Yu-Ning Zhang ◽  
Szu-Yuan Huang ◽  
Mong Liang
Keyword(s):  
Titanium Isopropoxide ◽  
Decomposition Temperature ◽  
Phenyl Isocyanate ◽  
Cross Linking ◽  
Resonance Spectroscopy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Melt Polycondensation ◽  
Structural Regularity

A series of N-substituted polyether-block-amide (PEBA-X%) copolymers were prepared by melt polycondensation of nylon-6 prepolymer and polytetramethylene ether glycol at an elevated temperature using titanium isopropoxide as a catalyst. The structure, thermal properties, and crystallinity of PEBA-X% were investigated using nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, wide angle X-ray diffraction, and thermogravimetric analysis. In general, the crystallinity, melting point, and thermal degradation temperature of PEBA-X% decreased as the incorporation of N-methyl functionalized groups increased, owing to the disruption caused to the structural regularity of the copolymer. However, in N-acetyl functionalized analogues, the crystallinity first dropped and then increased because of a new γ form arrangement that developed in the microstructure. After the cross-linking reaction of the N-methyl-substituted derivative, which has electron-donating characteristics, with poly(4,4′-methylenebis(phenyl isocyanate), the decomposition temperature of the resulting polymer significantly increased, whereas no such improvements could be observed in the case of the electro-withdrawing N-acetyl-substituted derivative, because of the incompleteness of its cross-linking reaction.

Temperature-induced structural phase transitions in RERhSn (RE = Y, Gd-Tm, Lu)

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Simon Engelbert ◽  
Rolf-Dieter Hoffmann ◽  
Jutta Kösters ◽  
Steffen Klenner ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Phase Transitions ◽  
Driving Force ◽  
Room Temperature ◽  
Structural Phase ◽  
Structural Phase Transitions ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray

Abstract The structures of the equiatomic stannides RERhSn with the smaller rare earth elements Y, Gd-Tm and Lu were reinvestigated on the basis of temperature-dependent single crystal X-ray diffraction data. GdRhSn crystallizes with the aristotype ZrNiAl at 293 and 90 K. For RE = Y, Tb, Ho and Er the HP-CeRuSn type (approximant with space group R3m) is already formed at room temperature, while DyRhSn adopts the HP-CeRuSn type below 280 K. TmRhSn and LuRhSn show incommensurate modulated variants with superspace groups P31m(1/3; 1/3; γ) 000 (No. 157.1.23.1) (γ = 3/8 for TmRhSn and γ = 2/5 for LuRhSn). The driving force for superstructure formation (modulation) is a strengthening of Rh–Sn bonding. The modulation is expressed in a 119Sn Mössbauer spectrum of DyRhSn at 78 K through line broadening.

The Relative Merits of Oxides of Hafnium, Cerium and Thorium as Surrogates for Plutonium Oxide in Calcium Phosphate Ceramics

2009 ◽  
Vol 1193 ◽  
Author(s):  
B. L. Metcalfe ◽  
S. K. Fong ◽  
L. A. Gerrard ◽  
I. W. Donald ◽  
E. S. Welch ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcination Temperature ◽  
Cerium Oxide ◽  
Absorption Spectroscopy ◽  
Hafnium Oxide ◽  
Intermediate Level ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption ◽  
Additional Phase

AbstractThe choice of surrogate for plutonium oxide for use during the initial stages of research into the immobilization of intermediate level pyrochemical wastes containing plutonium andamericium oxides in a calcium phosphate host has been investigated by powder X-ray diffraction and X-ray absorption spectroscopy. Two non-radioactive surrogates, hafnium oxide and cerium oxide, together with radioactive thorium oxide were compared. Similarities in behaviour were observed for all three surrogates when calcined at the lowest temperature, 750°C but differences became more pronounced as the calcination temperature was increased to 950°C. Although some reaction occurred between all the surrogates and the host to form a substituted whitlockite phase, increasing the temperature led to a significant increase in the cerium reaction and the formation of an additional phase, monazite. Additionally it was observed that the cerium became increasingly trivalent at higher temperatures.

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