scholarly journals Comment on ‘Multilayered Stable 2D Nano-Sheets of Ti2NTx MXene: Synthesis, Characterization, and Anticancer Activity’

2020 ◽  
Author(s):  
Yitong Guo ◽  
Qianku Hu ◽  
Libo Wang ◽  
Aiguo Zhou
Keyword(s):  
Anticancer Activity ◽  
Diffraction Pattern ◽  
Hydrofluoric Acid ◽  
Recent Article ◽  
Room Temperature ◽  
Max Phase ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray

<p>A recent article entitled “Multilayered stable 2D nano-sheets of Ti<sub>2</sub>NT<sub>x</sub> MXene: synthesis, characterization, and anticancer activity” published in this journal, claimed that two-dimensional Ti<sub>2</sub>NT<sub>x</sub> MXene could be synthesized by selectively etching Ti<sub>2</sub>AlN in concentrated hydrofluoric acid at room temperature. However, the X-ray diffraction pattern of Ti<sub>2</sub>NT<sub>x</sub> MXene reported in that paper is completely different with those of other MXenes. In this comment, it is argued that the samples synthesized in that paper were NOT Ti<sub>2</sub>NT<sub>x</sub> MXene at all. Although carbide MXenes can be made by selectively etching A layers from MAX phase, it is very difficult or impossible to make nitride MXenes (Ti<sub>2</sub>NT<sub>x</sub>) by the same way.</p>

scholarly journals Comment on ‘Multilayered Stable 2D Nano-Sheets of Ti2NTx MXene: Synthesis, Characterization, and Anticancer Activity’

2020 ◽  
Author(s):  
Yitong Guo ◽  
Qianku Hu ◽  
Libo Wang ◽  
Aiguo Zhou
Keyword(s):  
Anticancer Activity ◽  
Diffraction Pattern ◽  
Hydrofluoric Acid ◽  
Recent Article ◽  
Room Temperature ◽  
Max Phase ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray

<p>A recent article entitled “Multilayered stable 2D nano-sheets of Ti<sub>2</sub>NT<sub>x</sub> MXene: synthesis, characterization, and anticancer activity” published in this journal, claimed that two-dimensional Ti<sub>2</sub>NT<sub>x</sub> MXene could be synthesized by selectively etching Ti<sub>2</sub>AlN in concentrated hydrofluoric acid at room temperature. However, the X-ray diffraction pattern of Ti<sub>2</sub>NT<sub>x</sub> MXene reported in that paper is completely different with those of other MXenes. In this comment, it is argued that the samples synthesized in that paper were NOT Ti<sub>2</sub>NT<sub>x</sub> MXene at all. Although carbide MXenes can be made by selectively etching A layers from MAX phase, it is very difficult or impossible to make nitride MXenes (Ti<sub>2</sub>NT<sub>x</sub>) by the same way.</p>

On the tetragonality of the room-temperature ferroelectric phase of barium titanate, BaTiO3

2009 ◽  
Vol 42 (3) ◽  
pp. 480-484 ◽  
Author(s):  
Dean S. Keeble ◽  
Pamela A. Thomas
Keyword(s):  
Barium Titanate ◽  
Diffraction Pattern ◽  
Room Temperature ◽  
Ferroelectric Material ◽  
Tetragonal Symmetry ◽  
Temperature Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Group Assignment ◽  
Growth Method

The room-temperature phase of the important ferroelectric material barium titanate, BaTiO3, was re-investigated by single-crystal X-ray diffraction on a sample grown by the top-seeded solution growth method, with the intention of demonstrating once again that the structure has tetragonal symmetry consistent with the space-group assignmentP4mmand thus resolving recent controversy in the scientific community and literature [Yoshimura, Kojima, Tokunaga, Tozaki & Koganezawa (2006).Phys. Lett. A,353, 250–254; Yoshimura, Morioka, Kojima, Tokunaga, Koganezawa & Tozaki (2007).Phys. Lett. A,367, 394–401]. To this end, the X-ray diffraction pattern of a small (341 µm3) sample of top-seeded solution-grown BaTiO3was measured using an Oxford Diffraction Gemini CCD diffractometer employing Mo Kα radiation and an extended 120 mm sample-to-detector distance. More than 104individual diffraction maxima observed out to a maximum resolution of 0.4 Å were indexed on two tetragonal lattices. These were identical to within the standard deviations on the lattice parameters and were related to each other by a single rotation of 119.7° about the [11\overline1] direction of the first tetragonal lattice (the major twin component), although the actual twinning operation that explains the observed diffraction pattern both qualitatively and quantitatively is shown to be conventional 90° twinning by them[101] operation. Importantly, it is not necessary to invoke either monoclinic symmetry or a coexistence of tetragonal and monoclinic phases to explain the observed diffraction data.

Investigation of Ti3SiC2 MAX Phase Formation onto N-Type 4H-SiC

2012 ◽  
Vol 717-720 ◽  
pp. 845-848 ◽  
Author(s):  
Alexia Drevin-Bazin ◽  
Jean François Barbot ◽  
Thierry Cabioc’h ◽  
Marie France Beaufort
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
High Vacuum ◽  
Max Phase ◽  
Vacuum System ◽  
X Ray Diffraction ◽  
X Ray ◽  
Annealing Temperatures ◽  
Transmission Electron

In this study, investigations on MAX phase Ti3SiC2 formation to n-type 4H-SiC substrates and its ohmic-behaved are reported. Ti-Al layers were deposited onto SiC substrates at room temperature by magnetron sputtering in high vacuum system. Thermal annealing at 1000°C in Ar atmosphere were performed to allow interdiffusion processes. X-ray diffraction and High Resolution Transmission Electron Microscopy reveal that a Ti3SiC2 contact, in perfect epitaxy with 4H-SiC substrate, is so-obtained. In situ annealing experiment underlines the evolution of Ti-Al contact microstructure versus temperature. The evolution of contact system from Schottky to Ohmic behaved is observed by I-V measurements for annealing temperatures larger than 700°C.

Algorithms of Two-Dimensional X-Ray Diffraction

MRS Advances ◽  
2016 ◽  
Vol 1 (26) ◽  
pp. 1921-1927
Author(s):  
Bob B. He
Keyword(s):  
Diffraction Pattern ◽  
Intensity Distribution ◽  
Structure Refinement ◽  
Azimuthal Angle ◽  
Bragg Angle ◽  
Phase Identification ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Diffraction Vector ◽  
X Ray

ABSTRACTX-ray diffraction pattern collected with two-dimensional detector contains the scattering intensity distribution as a function of two orthogonal angles. One is the Bragg angle 2θ and the other is the azimuthal angle about the incident x-ray beam, denoted by γ. A 2D diffraction pattern can be integrated to a conventional diffraction pattern and evaluated by most exiting software and algorithms for conventional applications, such as, phase identification, structure refinement and 2θ-profile analysis. However, the materials structure information associated to the intensity distribution along γ direction is lost through the integration. The diffraction vector approach has been approved to be the genuine theory in 2D data analysis. The unit diffraction vector used for 2D analysis is a function of both 2θ and γ. The unit diffraction vector for all the pixels in the 2D pattern can be expressed either in the laboratory coordinates or in the sample coordinates. The vector components can then be used to derive fundamental equations for many applications, including stress, texture, crystal orientation and crystal size evaluation.

X-ray powder diffraction study on ErNi2Ge2

1999 ◽  
Vol 14 (2) ◽  
pp. 145-146
Author(s):  
Liangqin Nong ◽  
Lingmin Zeng
Keyword(s):  
Least Squares ◽  
Diffraction Study ◽  
Diffraction Pattern ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Rietveld Analysis ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray

An X-ray diffraction pattern for ErNi2Ge2 at room temperature is reported. ErNi2Ge2 is tetragonal with lattice parameters a=4.0191(2) Å, c=9.7643(2) Å, space group I4/mmm, and Z=2. The lattice parameters derived from Rietveld analysis agree well with the results of a least-squares refinement.

Room temperature recrystallization of nanocrystalline thin copper foils

1994 ◽  
Vol 362 ◽  
Author(s):  
J. Dille ◽  
J.-L. Delplancke ◽  
J. Charlier ◽  
R. Winand
Keyword(s):  
Electron Microscopy ◽  
Diffraction Pattern ◽  
Room Temperature ◽  
Structural Evolution ◽  
Preferential Orientation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Copper Foils ◽  
Different Temperatures ◽  
Anodized Titanium

AbstractThin copper foils (100 micrometers thick) are produced by electrolysis on anodized titanium substrates. A sharp distribution of grain diameter is observed around 200 nanometers. The X-ray diffraction pattern shows a slight preferential orientation of the crystals with the (111) planes parallel to the substrate. This X-ray diffraction pattern evolves at room temperature. After 60 days, a preferential orientation of the (200) planes parallel to the substrate is observed. This effect is associated with the recrystallisation of the foil with growth of large copper grains (diameter higher than 5 micrometers) as observed by high resolution transmission electron microscopy.The structural evolution of the copper foils is studied by electron microscopy, X-ray and electron diffractions at different temperatures.The mechanical properties of the foils are also studied as a function of time after electrodeposition.

Crystal structure and photoluminescence of a new two-dimensional Cd(II) coordination polymer based on 3-(carboxymethoxy)-2-naphthoic acid

2015 ◽  
Vol 70 (8) ◽  
pp. 605-608
Author(s):  
Zhi-Guo Kong ◽  
Sheng-Nan Guo ◽  
Jia-Qi Miao ◽  
Miao An
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Coordination Polymer ◽  
Room Temperature ◽  
Monoclinic Space Group ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Network ◽  
Naphthoic Acid

AbstractA new Cd(II) coordination polymer, [Cd(CNA)]n (1) (H2CNA = 3-(carboxymethoxy)-2-naphthoic acid), was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The crystals are monoclinic, space group P21/c with a = 16.9698(18), b = 7.8314(8), c = 8.9553(10) Å, β = 100.657(2)°, V = 1169.6(2) Å3, Z = 4, Dcalcd. = 2.03 g cm−3, μ(MoKα) = 1.9 mm−1, F(000) = 696 e, R = 0.0305, wR = 0.0784 for 172 refined parameters and 2285 data. Each CNA anion bridges three Cd(II) cations to give rise to a two-dimensional network structure. Topologically, if each CNA anion is regarded as a linker, and each Cd(II) atom considered as a 4-conencted node, the structure is simplified as a 4-connected (4,4) network. The solid state photoluminescent properties of the compound were also studied at room temperature.

scholarly journals Highly ordered polyaniline as an efficient dye remover

2017 ◽  
Vol 36 (1-2) ◽  
pp. 429-440 ◽  
Author(s):  
Pinki Chakraborty ◽  
Aman Kothari ◽  
Rajamani Nagarajan
Keyword(s):  
Electron Microscopy ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Diffraction Pattern ◽  
Fourier Transform Infrared Spectroscopy ◽  
Room Temperature ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

Polyaniline was synthesized by the chemical oxidative polymerization procedure at room temperature employing hydrogen peroxide (H2O2) as oxidant and ferrous chloride (FeCl2·2H2O) and vanadyl sulphate (VOSO4·H2O) as co-catalysts, respectively. The obtained polymers were characterized by high resolution powder X-ray diffraction, Fourier transform infrared spectroscopy, Raman, UV–Visible, photoluminescence spectroscopy, thermogravimetric Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) techniques. Ordered arrangement indicative of semi-crystalline nature of polyaniline was evidenced from the presence of intense reflection at d = 13.72 Å in the powder X-ray diffraction pattern followed by two lesser intense peaks at 4.61 and 3.47 Å. Fourier transform infrared spectroscopy and Raman spectroscopic results indicated the polyaniline to be emeraldine salt form. Fibrous morphology was observed in scanning electron microscope images. Nearly 93% of Methyl Orange dye was adsorbed in 30 min by the ordered polyaniline at room temperature. No significant difference in the crystallinity and/or ordering was noticed in the powder X-ray diffraction pattern after dye adsorption. The correlation between the ordered structure of polyaniline and its higher adsorption property derived in the current study has the potential to fabricate devices consisting polyaniline to detect dye molecules.

A two-dimensional coordination polymer: poly[diaqua(μ4-4,4′-oxydibenzoato)(μ2-4,4′-oxydibenzoato)dilead(II)]

2014 ◽  
Vol 70 (12) ◽  
pp. 1105-1108
Author(s):  
Xiao-Juan Xu
Keyword(s):  
Coordination Polymer ◽  
Room Temperature ◽  
Fluorescence Emission ◽  
Aqua Ligand ◽  
Two Dimensional ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Strong Fluorescence ◽  
X Ray ◽  
Point Symbol

In a new two-dimensional coordination polymer, [Pb(C14H8O5)(H2O)]n, the asymmetric unit consists of a PbIIcation, two halves of two crystallographically distinct fully deprotonated 4,4′-oxydibenzoate ligands and one aqua ligand. Single-crystal X-ray diffraction analysis reveals that the compound is a coordination polymer with the point symbol {53}2{54.82}. In addition, it exhibits a strong fluorescence emission in the solid state at room temperature.

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