Fabrication and Characterization of Electrospun Aligned Porous PAN/Graphene Composite Nanofibers

A modified parallel electrode method (MPEM), conducted by placing a positively charged ring between the needle and the paralleled electrode collector, was presented to fabricate aligned polyacrylonitrile/graphene (PAN/Gr) composite nanofibers (CNFs) with nanopores in an electrospinning progress. Two kinds of solvents and one kind of nanoparticle were used to generate pores on composite nanofibers. The spinning parameters, such as the concentration of solute and solvent, spinning voltage and spinning distance were discussed, and the optimal parameters were determined. Characterizations of the aligned CNFs with nanopores were investigated by scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), high-resistance meter, and other methods. The results showed that graphene (Gr) nanoparticles were successfully introduced into aligned CNFs with nanopores and almost aligned along the axis of the CNFs. The MPEM method could make hydrophobic materials more hydrophobic, and improve the alignment degree and conductive properties of electrospun-aligned CNFs with nanopores. Moreover, the carbonized CNFs with nanopores, used as an electrode material, had a smaller charge-transfer resistance, suggesting potential application in electrochemical areas and electron devices.

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Electrochemical Hydrogen Evolution over Hydrothermally Synthesized Re-Doped MoS2 Flower-Like Microspheres

Molecules ◽

10.3390/molecules24244631 ◽

2019 ◽

Vol 24 (24) ◽

pp. 4631 ◽

Cited By ~ 3

Author(s):

Juan Aliaga ◽

Pablo Vera ◽

Juan Araya ◽

Luis Ballesteros ◽

Julio Urzúa ◽

...

Keyword(s):

Electron Microscopy ◽

Hydrogen Evolution ◽

Photoelectron Spectroscopy ◽

Charge Transfer Resistance ◽

Chemical Analyses ◽

X Ray Diffraction ◽

Transfer Resistance ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

In this research, we report a simple hydrothermal synthesis to prepare rhenium (Re)- doped MoS2 flower-like microspheres and the tuning of their structural, electronic, and electrocatalytic properties by modulating the insertion of Re. The obtained compounds were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Structural, morphological, and chemical analyses confirmed the synthesis of poorly crystalline Re-doped MoS2 flower-like microspheres composed of few stacked layers. They exhibit enhanced hydrogen evolution reaction (HER) performance with low overpotential of 210 mV at current density of 10 mA/cm2, with a small Tafel slope of 78 mV/dec. The enhanced catalytic HER performance can be ascribed to activation of MoS2 basal planes and by reduction in charge transfer resistance during HER upon doping.

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PREPARATION AND CHARACTERIZATION OF A POLY(PYRROLYL METHANE)/MULTIWALLED CARBON NANOTUBES COMPOSITES

NANO ◽

10.1142/s179329201350063x ◽

2013 ◽

Vol 08 (06) ◽

pp. 1350063

Author(s):

JINXIAN LIN ◽

PAN WANG ◽

YUYING ZHENG

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Multiwalled Carbon Nanotubes ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Electrode System ◽

X Ray Diffraction ◽

Multiwalled Carbon ◽

Transfer Resistance ◽

Transmission Electron

A poly(pyrrolyl methane) (Poly[pyrrole-2, 5-diyl(4-methoxybenzylidane)], PPDMOBA)/multiwalled carbon nanotubes (MWNTs) composites are fabricated by in situ chemical polycondensation of pyrrole and 4-methoxybenzaldehyde on MWNTs. The structure, morphology, thermal stability and electrical property of the resulting composites are investigated via fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and a four-probe method. The electrochemical performance of the composites is determined in a three-electrode system using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS) techniques. FTIR, FESEM and TEM confirm that the composites have been successfully prepared, and PPDMOBA is uniformly dispersed in MWNTs. Electrical conductivity of PPDMOBA/MWNTs composites is 1.39 S cm-1, which is significantly larger than that of pristine PPDMOBA. The specific capacitance and charge transfer resistance of the composites is 56 F g-1 (1 mA cm-2) and 0.3Ω, respectively.

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Synthesis, Characterization, and Photocatalytic Performance of Mesoporous α-Mn2O3 Microspheres Prepared via a Precipitation Route

Journal of Nanoparticles ◽

10.1155/2016/8037013 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 8

Author(s):

Manoj Pudukudy ◽

Zahira Yaakob

Keyword(s):

Electron Microscopy ◽

Uv Light ◽

Thermal Transformation ◽

Xrd Analysis ◽

Structural Deformation ◽

Blue Dye ◽

X Ray Diffraction ◽

Electron Microscopic ◽

X Ray ◽

Transmission Electron

α-Mn2O3 microspheres with high phase purity, crystallinity, and surface area were synthesized by the thermal decomposition of precipitated MnCO3 microspheres without the use of any structure directing agents and tedious reaction conditions. The prepared Mn2O3 microspheres were characterized by Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) and photoluminescence (PL) studies. The complete thermal transformation of MnCO3 to Mn2O3 was clearly shown by the FTIR and XRD analysis. The electron microscopic images clearly confirmed the microsphere-like morphology of the products with some structural deformation for the calcined Mn2O3 sample. The mesoporous texture generated from the interaggregation of subnanoparticles in the microstructures is visibly evident from the TEM and BET studies. Moreover, the Mn2O3 microstructures showed a moderate photocatalytic activity for the degradation of methylene blue dye pollutant under UV light irradiation, using air as the potential oxidizing agent.

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Hydrothermal Synthesis of MnWO4@GO Composite as Non-Precious Electrocatalyst for Urea Oxidation

Nanomaterials ◽

10.3390/nano12010085 ◽

2021 ◽

Vol 12 (1) ◽

pp. 85

Author(s):

Patnamsetty Chidanandha Nagajyothi ◽

Kisoo Yoo ◽

Rajavaram Ramaraghavulu ◽

Jaesool Shim

Keyword(s):

Electron Microscopy ◽

Hydrothermal Synthesis ◽

Photoelectron Spectroscopy ◽

Xrd Analysis ◽

Morphological Characterization ◽

Energy Storage And Conversion ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Density Values

In this study, manganese tungstate (MW) and MW/graphene oxide (GO) composites were prepared by a facile hydrothermal synthesis at pH values of 7 and 12. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy were used for the structural, compositional, and morphological characterization of the nanoparticles (NPs). The XRD analysis revealed that the formation of monoclinic MnWO4 did not have impurities. The SEM and TEM analyses showed that the synthesized NPs were rod-shaped and well-distributed on the GO. The as-synthesized samples can be used as electrocatalysts for the urea oxidation reaction (UOR). The MW@GO-12 electrocatalyst exhibited higher current density values compared to other electrocatalysts. This study provides a new platform for synthesizing inexpensive nanocomposites as promising electrocatalysts for energy storage and conversion applications.

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Enhancement of durability of NIR emission of Ag2S@ZnS QDs in water

Modern Physics Letters B ◽

10.1142/s0217984917502979 ◽

2017 ◽

Vol 31 (32) ◽

pp. 1750297 ◽

Cited By ~ 2

Author(s):

M. Karimipour ◽

M. Bagheri ◽

M. Molaei

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Xrd Analysis ◽

Core Shell ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Nir Emission ◽

Core Shell Structure ◽

Phase Transmission

Stability of Ag2S@ZnS QDs in water is a crucial concern for their application in biology. In this work, both physical sustainability and emission stability of Ag2S QDs were enhanced using parameter optimization of a pulsed microwave irradiation (MI) method up to 105 days after their preparation. UV–Vis and photoluminescence spectroscopies depicted an absorption and emission about 817 nm and 878 nm, respectively. X-ray diffraction (XRD) analysis showed a growth of Ag2S acanthite phase. Transmission Electron Microscopy (TEM) images revealed a clear formation of Ag2S@ZnS core–shell structure.

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Study on the Growth Mechanism of K2Ti4O9 Crystal

High Temperature Materials and Processes ◽

10.1515/htmp-2016-0168 ◽

2018 ◽

Vol 37 (5) ◽

pp. 405-410

Author(s):

Xuesong Zhou ◽

Jing Fan ◽

Xiaoli Wei ◽

Yi Shen ◽

Yanzhi Meng

Keyword(s):

Electron Microscopy ◽

Growth Mechanism ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Calcination Temperatures ◽

Transmission Electron ◽

Transformation Reaction ◽

Calcination Method ◽

Potassium Hexatitanate ◽

Parallel Action

AbstractPotassium hexatitanate (K2Ti4O9) whiskers were prepared by the kneading–drying–calcination method. After the preparation of products under different calcination temperatures and holding times, their morphology and structure were characterized by thermogravimetric and differential thermal, X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy. The XRD analysis showed that the reaction mixture was completely converted to K2Ti4O9 crystals at 800 °C when the T/K ratio was 3. Based on the analysis of LS (liquid–solid) growth mechanism, the corresponding transformation reaction mechanism during the roasting was elucidated. K2Ti4O9 whiskers grow mainly through the parallel action at a low temperature. With the increase in temperature, the series effect is obvious.

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Synthesis and Characterization of Nano Hydroxylapatite by Reaction Precipitation in Impinging Streams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.1301 ◽

2010 ◽

Vol 160-162 ◽

pp. 1301-1308 ◽

Cited By ~ 3

Author(s):

Jun Yuan ◽

Yuan Wu ◽

Qi Xin Zheng ◽

Xiao Lin Xie

Keyword(s):

Electron Microscopy ◽

Xrd Analysis ◽

Synthesis And Characterization ◽

Preparation Process ◽

X Ray Diffraction ◽

Excellent Performance ◽

X Ray ◽

Operation Conditions ◽

Transmission Electron

Hydroxylapatite(HAP) nano-whiskers are prepared by reaction-precipitation in the submerged circulative impinging stream reactor(SCISR), with (NH4)2HPO4 and Ca(NO3)2 as the reagents; and the products are characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The results TEM measured indicate that the product prepared under typical operation conditions is average-sized 15nm and 50-70nm long. Multiply repeated experiments illustrates that, because of the excellent performance of the reactor, the preparation process can be easily controlled to yield nano rod/whisker hydroxylapatite with very narrow size distribution.

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Investigation of Lithiated Carbons by Transmission Electron Microscopy and X-Ray Diffraction Analysis

MRS Proceedings ◽

10.1557/proc-548-37 ◽

1998 ◽

Vol 548 ◽

Author(s):

T. D. Tran ◽

X. Y. Song ◽

K. Kinoshita

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Carbon Black ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Lattice Image ◽

X Ray ◽

Storage Mechanism ◽

Transmission Electron ◽

Diffraction Patterns

ABSTRACTThe microstructures of lithiated synthetic graphite and carbon black were studied by high- resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) analysis. Information about the crystal structure of carbon containing various Li compositions can provide useful insights to our understanding of the Li storage mechanism in carbonaceous materials. Samples with compositions of Li0.93C6or Li0.45C6 were found to contain both stage-one and stage-two compounds. These observations are consistent with XRD data. The changes in sample microstructure as the results of lithiation and exposure to electron irradiation were observed by TEM and recorded over several minutes in the microscope environment. Selected area electron diffraction patterns indicated that the lithiated samples quickly changed composition to LiC 24, which appeared to dominate during the brief analysis period. The layer planes in the lattice image of a disordered carbon black after Li insertion are poorly defined, and changes in the microstructure of these lithiated carbons was not readily apparent. Observations on these lithium intercalation compounds as well as the limitation of the experimental procedure will be presented.

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Functionalized Silicate Supported TiO2-ZnO Nanocomposite Film and its Application in Simultaneous Photocatalytic Degradation of Toxic Molecules

Materials Science Forum ◽

10.4028/www.scientific.net/msf.764.255 ◽

2013 ◽

Vol 764 ◽

pp. 255-265 ◽

Cited By ~ 1

Author(s):

R. Dhanalakshmi ◽

A. Pandikumar ◽

R. Ramaraj

Keyword(s):

Electron Microscopy ◽

Sol Gel ◽

Xrd Analysis ◽

Potential Candidate ◽

Reaction Products ◽

X Ray Diffraction ◽

Chemical Route ◽

Molar Ratios ◽

Amine Functionalized ◽

Transmission Electron

The TiO2-ZnO nanocomposite materials ((TiO2-ZnO)NCM) with different molar ratios (Ti:Zn) was synthesized by chemical route and dispersed in functionalized silicate sol-gel matrix (Silicate/(TiO2-ZnO)NCM)). The as prepared Silicate/(TiO2-ZnO)NCM were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The dispersion of the small amount of (TiO2-ZnO)NCM in silicate sol-gel matrix paves the way for the preparation of solid-state thin film photocatalyst which is advantageous for the separation of the catalyst from solution, the substrates and the reaction products. The simultaneous photoinduced oxidation of methylene blue (MB) dye and reduction of Cr (VI) to Cr (III) was examined at different amine functionalized silicate sol-gel embedded (TiO2-ZnO)NCM films. The (TiO2-ZnO)NCM dispersed into the amine functionalized silicate sol-gel matrix (TPDT) exhibited enhanced photocatalytic activity when compared to the (TiO2-ZnO)NCM without the silicate sol-gel. The functionalized silicate sol-gel supported (TiO2-ZnO)NCM is a potential candidate for energy conversion and environment remediation and cleaning applications.

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Preparation of Chrysotile Nanotubes under Hydrothermal Condition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.688 ◽

2011 ◽

Vol 284-286 ◽

pp. 688-691 ◽

Cited By ~ 1

Author(s):

Yang Feng Huang ◽

Ye Bin Cai ◽

Hao Liu

Keyword(s):

Electron Microscopy ◽

Hydrothermal Condition ◽

Xrd Analysis ◽

Outer Diameter ◽

X Ray Diffraction ◽

X Ray ◽

Structure And Morphology ◽

Transmission Electron ◽

Inner Diameter ◽

Temperature And Pressure

In a neutral environment, Chrysotile nanotubes have been synthesized by hydrothermal method, with MgO and SiO2powder as the starting materials. X-Ray Diffraction(XRD), Scanning Electron Microscopy(SEM), Transmission Electron Microscopy(TEM) are used to characterize the crystal structure and morphology of the as-prepared samples. We found that the diameter of Chrysotile is uniform. Their outer diameter is about 30~50 nm and the inner diameter is about 6~8 nm. The length of them is a few hundred nanometers. The XRD analysis indicates that the as-prepared Chrysotile is a Rhombohedral structures. The results of HRTEM and SAED showed that the {006} planes of serpentine roll up along the [600] direction to form the tubular structure. In addition, the curves of temperature and pressure with time showed that the water might participate in the reaction.

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