Band mapping in higher-energy x-ray photoemission: Phonon effects and comparison to one-step theory

Iridium-containing NaTaO3 is produced using a one-step hydrothermal crystallisation from Ta2O5 and IrCl3 in an aqueous solution of 10 M NaOH in 40 vol% H2O2 heated at 240 °C. Although a nominal replacement of 50% of Ta by Ir was attempted, the amount of Ir included in the perovskite oxide was only up to 15 mol%. The materials are formed as crystalline powders comprising cube-shaped crystallites around 100 nm in edge length, as seen by scanning transmission electron microscopy. Energy dispersive X-ray mapping shows an even dispersion of Ir through the crystallites. Profile fitting of powder X-ray diffraction (XRD) shows expanded unit cell volumes (orthorhombic space group Pbnm) compared to the parent NaTaO3, while XANES spectroscopy at the Ir LIII-edge reveals that the highest Ir-content materials contain Ir4+. The inclusion of Ir4+ into the perovskite by replacement of Ta5+ implies the presence of charge-balancing defects and upon heat treatment the iridium is extruded from the perovskite at around 600 C in air, with the presence of metallic iridium seen by in situ powder XRD. The highest Ir-content material was loaded with Pt and examined for photocatalytic evolution of H2 from aqueous methanol. Compared to the parent NaTaO3, the Ir-substituted material shows a more than ten-fold enhancement of hydrogen yield with a significant proportion ascribed to visible light absorption.

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A Versatile Approach to Access Trimetallic Complexes Based on Trisphosphinite Ligands

Molecules ◽

10.3390/molecules25030593 ◽

2020 ◽

Vol 25 (3) ◽

pp. 593

Author(s):

Juan Miranda-Pizarro ◽

Macarena G. Alférez ◽

M. Dolores Fernández-Martínez ◽

Eleuterio Álvarez ◽

Celia Maya ◽

...

Keyword(s):

Coordination Chemistry ◽

Late Transition Metal ◽

X Ray Diffraction ◽

X Ray ◽

Full Characterization ◽

Metal Precursors ◽

Straightforward Method ◽

One Step ◽

Late Transition

A straightforward method for the preparation of trisphosphinite ligands in one step, using only commercially available reagents (1,1,1-tris(4-hydroxyphenyl)ethane and chlorophosphines) is described. We have made use of this approach to prepare a small family of four trisphosphinite ligands of formula [CH3C{(C6H4OR2)3], where R stands for Ph (1a), Xyl (1b, Xyl = 2,6-Me2-C6H3), iPr (1c), and Cy (1d). These polyfunctional phosphinites allowed us to investigate their coordination chemistry towards a range of late transition metal precursors. As such, we report here the isolation and full characterization of a number of Au(I), Ag(I), Cu(I), Ir(III), Rh(III) and Ru(II) homotrimetallic complexes, including the structural characterization by X-ray diffraction studies of six of these compounds. We have observed that the flexibility of these trisphosphinites enables a variety of conformations for the different trimetallic species.

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Effect of the BSCCO superconducting properties by tiny Y2O3 addition

Modern Physics Letters B ◽

10.1142/s0217984916503280 ◽

2016 ◽

Vol 30 (26) ◽

pp. 1650328

Author(s):

Yan Dong ◽

Aimin Sun ◽

Bin Xu ◽

Hongtao Zhang ◽

Meng Zhang

Keyword(s):

Volume Fraction ◽

Superconducting Properties ◽

X Ray Diffraction ◽

Critical Transition Temperature ◽

Solid State Reaction Technique ◽

X Ray ◽

Oxide Addition ◽

One Step ◽

Step Transition ◽

Y2o3 Addition

In this paper, the effect of tiny Y2O3 addition in (Bi,[Formula: see text]Pb)-2223 superconductor prepared by solid state reaction technique was studied. The properties of samples have been investigated via X-ray diffraction (XRD), resistance–temperature ([Formula: see text]–[Formula: see text]) curve, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). XRD data indicated that all samples are multiphase and the major phases are high-temperature phases and low-temperature phases. The volume fraction of (Bi,[Formula: see text]Pb)-2223 is not great change with tiny Y2O3 addition. All samples exhibit superconducting phase with the critical transition temperature and one-step transition, however, the transition width was decreased with the Y2O3 addition up to 0.04 wt.% and sharp increased with the excessive oxide addition. SEM pictures show that the Y2O3 appeared on the flake-type grains surface obviously, but the number and size of the hole between grains are decreased in the 0.04 wt.% addition.

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One Step Synthesis and Characterization of Zirconia-Graphene Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.600.174 ◽

2012 ◽

Vol 600 ◽

pp. 174-177 ◽

Cited By ~ 1

Author(s):

Jian Fei Xia ◽

Zong Hua Wang ◽

Yan Zhi Xia ◽

Fei Fei Zhang ◽

Fu Qiang Zhu ◽

...

Keyword(s):

Synthesis And Characterization ◽

Two Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Graphene Composite ◽

Transmission Electron ◽

One Step ◽

Ft Ir ◽

Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

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Fabrication of Advanced Functional Devices Combining Soft Chemistry with X-ray Lithography in One Step

Advanced Materials ◽

10.1002/adma.200901561 ◽

2009 ◽

Vol 21 (48) ◽

pp. 4932-4936 ◽

Cited By ~ 51

Author(s):

Paolo Falcaro ◽

Luca Malfatti ◽

Lisa Vaccari ◽

Heinz Amenitsch ◽

Benedetta Marmiroli ◽

...

Keyword(s):

Soft Chemistry ◽

X Ray ◽

One Step

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Threefold Spiral Structure Constructed by 1D Chains of [[M(NCS)2(bpa)2]·biphenyl]n (M = Fe, Co; bpa = 1,2-bis(4-pyridyl)ethane)

Crystals ◽

10.3390/cryst9020097 ◽

2019 ◽

Vol 9 (2) ◽

pp. 97 ◽

Cited By ~ 1

Author(s):

Satoshi Tokinobu ◽

Haruka Dote ◽

Satoru Nakashima

Keyword(s):

Spin Crossover ◽

Spiral Structure ◽

Diffusion Method ◽

Central Metal ◽

X Ray ◽

Pyridine Complex ◽

1D Chain ◽

One Step ◽

Spiral Structures ◽

1D Chains

Assembled complexes [[M(NCS)2(bpa)2]·biphenyl]n (M = Fe, Co; bpa = 1,2-bis(4-pyridyl)ethane) have been synthesized because [Fe(NCBH3)2(bpa)2·biphenyl]n has a novel threefold spiral structure and shows stepwise spin-crossover phenomenon. We attempted to obtain spiral structures for [[Fe(NCS)2(bpa)2]·biphenyl]n and [[Co(NCS)2(bpa)2]·biphenyl]n using a one-step diffusion method, while the reported spiral structure of [[Fe(NCBH3)2(bpa)2]·biphenyl]n was obtained by diffusion method after synthesizing Fe(II)-pyridine complex. X-ray structural analysis revealed that [[Fe(NCS)2(bpa)2]·biphenyl]n and [[Co(NCS)2(bpa)2]·biphenyl]n had a chiral propeller structure of pyridines around the central metal, and they had a novel spiral structure and chiral space group P3121 without the presence of chiral auxiliaries. It was shown that the host 1D chain, having a chiral propeller structure of pyridines around the central metal along with its concerted interaction with an atropisomer of biphenyl, made a threefold spiral structure.

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Nanocrystal, phase transformation and microstructure of Ni50Ti50 shape memory alloy

Mongolian Journal of Agricultural Sciences ◽

10.5564/mjas.v24i02.1114 ◽

2018 ◽

Vol 24 (02) ◽

pp. 22-25

Author(s):

Dovchinvanchig M ◽

Chunwang Zhao

Keyword(s):

Differential Scanning Calorimetry ◽

Phase Transformation ◽

Shape Memory Alloy ◽

Shape Memory ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

One Step ◽

Niti Matrix ◽

Electronic Microscope

The nanocrystal, phase transformation and microstructure behavior of Ni50Ti50 shape memory alloy was investigated by scanning electronic microscope, X-ray diffraction and differential scanning calorimetry. The results showed that the microstructure of Ni-Ti binary alloy consists of the NiTi2 phase and the NiTi matrix phase. One-step phase transformation was observed alloy.

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Low-temperature hydrothermal synthesis of hierarchical flower-like CuB2O4 superstructures

Processing and Application of Ceramics ◽

10.2298/pac2002113u ◽

2020 ◽

Vol 14 (2) ◽

pp. 113-118

Author(s):

Daniel Ursu ◽

Anamaria Dabici ◽

Marinela Miclau ◽

Nicolae Miclau

Keyword(s):

Thermal Stability ◽

Low Temperature ◽

Self Assembly ◽

Hydrothermal Solution ◽

Optical Measurements ◽

Oriented Attachment ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

One Step

We report for the first time the fabrication of hierarchical ordered superstructure CuB2O4 with flower-like morphology via a one-step, low temperature hydrothermal method. The tetragonal structure of CuB2O4 was determined by X-ray diffraction and high-resolution transmission electron microscopy. Optical measurements attested of the quality of the fabricated CuB2O4 and high temperature X-ray diffraction confirmed its thermal stability up to 600 ?C. The oriented attachment growth and the hierarchical self-assembly of micrometer-sized platelets producing hierarchical superstructures with flower-like morphology are designed by pH of the hydrothermal solution. The excellent band gap, high thermal stability and hierarchical structure of the CuB2O4 are promising for the photovoltaic and photocatalytic applications.

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Ultraviolet and violet-blue emission of Zn doped MgO/mg(OH)2 particles prepared by one step spray pyrolysis method

Journal of Powder Technology and Advanced Functional Materials ◽

10.29253/jptafm.v1i1.8 ◽

2018 ◽

Vol 1 (1) ◽

pp. 57-66

Author(s):

Fenfen Fenda Florena ◽

◽

Dwindra Wilham Maulana ◽

Ferry Faizal ◽

Bambang Mukti Wibawa ◽

...

Keyword(s):

Spray Pyrolysis ◽

Doping Concentration ◽

Blue Emission ◽

Spherical Shape ◽

Spherical Particles ◽

Spray Pyrolysis Method ◽

Excitation Spectra ◽

X Ray ◽

Pyrolysis Method ◽

One Step

Spherical particles of Zn doped MgO were prepared by one-step spray pyrolysis method. The crystalline nature and particle size of the samples were characterized by X-ray diffraction analysis (XRD). The morphology of samples was studied by scanning electron microscope (SEM) and the presence of Zn in the sample was confirmed by energy dispersive X-ray analysis (EDX). The optical properties of the samples were investigated using photoluminescence spectroscopy (PL) analysis to obtain excitation and emission spectra of the samples. Results indicated that the doped MgO particles exhibited a cubic structure without hexagonal wurtzite structure as the Zn concentrations were increased. Spherical shape and porous particles are found with increasing of doping concentration. The optical band gap of MgO altered with the addition of doping concentration. A considerable redshift of about ~0.08 – 0.13 eV in the excitation spectra of 2.22 eV emission band was revealed in Zn doped MgO samples. It was highlighted that Zn doped MgO prepared by the spray pyrolysis generated emission at UV-Vis wavelength required for many applications.

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Hierarchical Nanostructured ZnO-CuO Nanocomposite and its Photocatalytic Activity

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.35.21 ◽

2015 ◽

Vol 35 ◽

pp. 21-26 ◽

Cited By ~ 16

Author(s):

Susmita Das ◽

Vimal Chandra Srivastava

Keyword(s):

Photocatalytic Activity ◽

Pure Copper ◽

Ultra Violet ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Ultra Violet Radiation ◽

One Step ◽

Uv Visible

Metal oxide nanocomposite (ZnO-CuO) was successfully synthesized by one step homogeneous coprecipitation method and further characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), X-ray diffraction analysis (XRD) and UV-visible diffuse reflectance spectra. XRD analysis exhibited presence of pure copper oxide and zinc oxide within the nanocomposite. SEM analysis indicated that the ZnO-CuO nanocomposite was consisted of flower shaped ZnO along with leaf shaped CuO. Photocatalytic activity of nanocomposite was evaluated in terms of degradation of methylene blue (MB) dye solution under ultra-violet radiation. Results showed that the photocatalytic efficiency of ZnO-CuO nanocomposite was higher than its individual pure oxides (ZnO or CuO).

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