High-Temperature Performance of Amorphous Nickel Hydroxide Coated with La(OH)3

2011 ◽  
Vol 311-313 ◽  
pp. 1365-1369
Author(s):  
Chang Jiu Liu ◽  
Mei Rong Qi ◽  
Chun Xiao Xing
Keyword(s):  
High Temperature ◽  
Nickel Hydroxide ◽  
Electrochemical Impedance ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Transfer Resistance ◽  
X Ray ◽  
Temperature Performance ◽  
Chemical Coprecipitation Method ◽  
Electron Transfer Resistance

La(OH)3coated amorphous nickel hydroxide was prepared by chemical coprecipitation method. The microstructure, surface morphology and chemical composition of the prepared sample were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). Electrochemical performances of the sample were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge measurements. The results demonstrated that the coating of La(OH)3 dramatically decreased electron transfer resistance and increased oxygen evolution potential of amorphous nickel hydroxide. Moreover, the high-temperature performance of amorphous nickel hydroxide was significantly improved after the coating of La(OH)3.

Effect of Zirconium Oxide Reinforcement on Microstructural, Electrochemical and Mechanical Properties of TiNi Alloy Produced Via Powder Metallurgy Route

2021 ◽  
pp. 1-22
Author(s):  
Syed Abbas Raza ◽  
Muhammad Imran Khan ◽  
Muhammad Ramzan Abdul karim ◽  
Rashid Ali ◽  
Muhammad Umair Naseer ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Passive Layer ◽  
Charge Transfer Resistance ◽  
Tini Alloy ◽  
X Ray Diffraction ◽  
Zro2 Content ◽  
Transfer Resistance ◽  
X Ray ◽  
Conventional Sintering ◽  
Layer Resistance

Abstract Equiatomic TiNi alloy composites, reinforced with 0, 5, 10 and 15 vol. % ZrO2, were synthesized using conventional sintering approach. Equiatomic TiNi pre-alloyed powder and ZrO2 powder were mixed in planetary ball mill for 6 hours followed by cold compaction and pressure-less sintering, respectively. The sintered density was found to vary inversely with the addition of ZrO2 content. The X-Ray diffraction spectra have shown the formation of multiple-phases which were resulted from the decomposition of the B19'and B2 phases of the equiatomic TiNi alloy due to the addition of ZrO2 and higher diffusion rate of Ni than that of Ti in the alloy composite. An increase in hardness was noted due to the addition of ZrO2, measured by micro and nanoindentation techniques. Potentiodynamic polarization scan revealed a 10% decrease in the corrosion rate of the composite containing 10 vol. % ZrO2. Electrochemical impedance spectroscopy results indicated an increase in passive layer resistance (Rcoat) due to the increase in charge transfer resistance (Rct) caused by the reduced leaching of ions from the surface.

Modification of Asphalt by Montmorillonite

2011 ◽  
Vol 84-85 ◽  
pp. 662-666 ◽  
Author(s):  
Zeng Ping Zhang ◽  
Yong Wen ◽  
Jian Zhong Pei ◽  
Shuan Fa Chen
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Temperature Sensitivity ◽  
Softening Point ◽  
High Speed ◽  
Melt Blending ◽  
X Ray Diffraction ◽  
Nanocomposite Structure ◽  
X Ray ◽  
Temperature Performance

Montmorillonite (MMT) modified asphalts are prepared by melt blending with the help of high-speed shear mixer. The dispersion of MMT layers in the asphalt matrix are characterized by X-ray diffraction (XRD). The effect of different contents of MMT on physical properties of the base asphalt is studied. These properties include penetration, softening point and ductility. The results indicate that MMT/asphalt may form a nanocomposite structure with MMT layers intercalated by the asphalt molecules. MMT can improve the high temperature performance and temperature sensitivity of the base asphalt. And it can slightly reduce the low temperature performances of matrix asphalt. It is found that low temperature performances, high temperature performance and temperature sensitivity of the modified system achieved balance when the content of MMT is 4 wt%.

PREPARATION AND INVESTIGATION OF ELECTRODEPOSITED Ni–NANO-Cr2O3 COMPOSITE COATINGS

2016 ◽  
Vol 23 (02) ◽  
pp. 1550111 ◽  
Author(s):  
JIBO JIANG ◽  
CHENQI FENG ◽  
WEI QIAN ◽  
LIBIN YU ◽  
FENGYING YE ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Composite Coatings ◽  
Charge Transfer Resistance ◽  
X Ray Diffraction ◽  
Transfer Resistance ◽  
X Ray ◽  
Potentiodynamic Polarization Curves ◽  
Nucleation Sites ◽  
Passive Transition ◽  
Steel Surfaces

The electrodeposition of Ni–nano-Cr2O3 composite coatings was studied in electrolyte containing different contents of Cr2O3 nanoparticles (Cr2O3 NPs) on mild steel surfaces. Some techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness, the potentiodynamic polarization curves (Tafel) and electrochemical impedance spectroscopy (EIS) were used to compare pure Ni coatings and Ni–nano-Cr2O3 composite coatings. The results show that the incorporation of Cr2O3 NPs resulted in an increase of hardness and corrosion resistance, and the maximum microhardness of Ni-nano-Cr2O3 composite coatings reaches about 495 HV. The coatings exhibit an active-passive transition and relatively large impedance values. Moreover, the effect of Cr2O3 NPs on Ni electrocrystallization is also investigated by cyclic voltammetry (CV) and EIS spectroscopy, which demonstrates that the nature of Ni-based composite coatings changes attributes to Cr2O3 NPs by offering more nucleation sites and less charge transfer resistance.

Electrochemical Performances of Yttrium Doped Li3V2–XYX(PO4)3/C Cathode Material for Lithium Secondary Battery

2015 ◽  
Vol 15 (10) ◽  
pp. 8042-8047 ◽  
Author(s):  
Minchan Jeong ◽  
Hyun-Soo Kim ◽  
Dong-Sik Bae ◽  
Chang-Woo Lee ◽  
Bong-Soo Jin
Keyword(s):  
Electrochemical Impedance ◽  
Rate Capability ◽  
Cycling Performance ◽  
Charge Transfer Resistance ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Lithium Secondary Battery ◽  
Capacity Retention ◽  
Solid State Method ◽  
Transfer Resistance

In this study, the Li3V2–X YX(PO4)3 compounds have been synthesized by a simple solid state method. In addition, a polyurethane was added to apply carbon coating on the surface of the Li3V2–X YX(PO4)3 particles for enhancement of the electrical conductivity. The crystal structure and morphology of the synthesized Li3V2–XYX(PO4)3/C (LVYP/C) was investigated using an X-ray diffraction (XRD) and a scanning electron microscopy (SEM) systematically. The electrochemical performance of synthesized material, such as the initial capacity, rate capability, cycling performance and EIS was evaluated. The sizes of synthesized particle ranged from 1 to 5 μm. The Li3V2–XYX(PO4)3/C (X = 0.02) delivered the initial discharge capacity of 171.5 mAh · g–1 at 0.1C rate. It showed a capacity retention ratio of 73.0% at 1.0C after 100th cycle. The electrochemical impedance spectroscopies (EIS) results revealed that the charge transfer resistance of the material decreases by Y doping.

Structure and Performance of Calcined Bauxite

2014 ◽  
Vol 887-888 ◽  
pp. 305-308 ◽  
Author(s):  
Bin Zheng Fang ◽  
Hui Li ◽  
Jian Wei Cao ◽  
Jian Feng Wu ◽  
Xiao Hong Xu ◽  
...  
Keyword(s):  
High Temperature ◽  
Heat Storage ◽  
X Ray Diffraction ◽  
Storage Material ◽  
X Ray ◽  
Temperature Performance ◽  
Heat Storage Material ◽  
Testing Technology ◽  
Crystal Phases ◽  
And Performance

In order to further broaden the application field of calcined bauxite, using differential thermal analysis-thermo-gravimetry (DTA-TG), X-ray diffraction analysis (XRD), Scanning electron microscopy (SEM) and other testing technology to study and analysis on the high temperature performance of calcined bauxite in this paper. The results show that the main crystal phases of calcined bauxite are corundum and mullite, appearance is layered, granular distribution. Due to the thermal performance of calcined bauxite is optimal, and is expected to be used for the field of high temperature solar thermal heat storage material.

Microwave Involved Synthesis of Graphene/Polyaniline Nanocomposite with Superior Electrochemical Performance

2017 ◽  
Vol 46 ◽  
pp. 212-224 ◽  
Author(s):  
Han Xun Qiu ◽  
Xue Bing Han ◽  
Jing Li ◽  
Fei Long Qiu ◽  
Jun He Yang
Keyword(s):  
Electrochemical Impedance ◽  
In Situ Polymerization ◽  
Photoelectron Spectra ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Galvanostatic Charge ◽  
X Ray ◽  
Energy Storage Applications ◽  
Polyaniline Nanocomposite

A microwave irradiation involved process was applied to fabrication of graphene/polyaniline nanocomposite via in-situ polymerization of aniline monomers on graphene sheets. Structure and morphology of composites were characterized through scanning electron microscopy, Raman spectra, X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectra. Electrochemical performances for energy storage applications were examined by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge/discharge measurements. Owing to the homogeneous coating of polyanilline on the large surface of graphene, graphene/polyaniline composite-based electrode exhibits remarkably enhanced capacitive behavior with a specific capacitance of 429 F/g at 0.2 A g-1, a good cyclic stability and an excellent conducting behavior, which are much superior to those of individual components of composites. The improved electrochemical behavior of the composite resulting from the irradiation of microwave suggests the promising potentials for supercapacitors.

High temperature X-ray diffraction investigation of an aluminium-silicon-corundum system

2007 ◽  
Vol 2007 (suppl_26) ◽  
pp. 369-374 ◽  
Author(s):  
D. Garipoli ◽  
P. Bergese ◽  
E. Bontempi ◽  
M. Minicucci ◽  
A. Di Cicco ◽  
...  
Keyword(s):  
High Temperature ◽  
X Ray Diffraction ◽  
X Ray

Effect of Zn Content on Structure, Roughness and Corrosion Behavior of Zn-Ni Alloys

2019 ◽  
Vol 17 (17) ◽  
pp. 17-22
Author(s):  
Hayette Faid
Keyword(s):  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Stripping Voltammetry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ni Alloys ◽  
Sulfate Bath ◽  
Zn Content ◽  
Polarization Test ◽  
Δ Phase

AbstractIn this work, Zn-Ni alloys have been deposited on steel from sulfate bath, by electrodeposition method. The effect of Zn content on deposits properties was studied by cyclic voltammetry (CV), chronoaperometry (CA), linear stripping voltammetry (ALSV) and diffraction (XRD) and scanning electronic microscopy (SEM). The corrosion behavior in 3.5 wt. NaCl solution was examined using anodic polarization test and electrochemical impedance spectroscopy. X-ray diffraction of show that Zn-Ni alloys structure is composed of δ phase and γ phase, which increase with the decrease of Zn content in deposits. Results show that deposits obtained from bath less Zn2+ concentration exhibited better corrosion resistance.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim
Keyword(s):  
Ionic Conductivity ◽  
Electrochemical Impedance ◽  
Structural Information ◽  
Impedance Analysis ◽  
High Energy ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Powder Morphology ◽  
X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

scholarly journals High-pressure synthesis and crystal structure of the mixed-cation borate Ga4In4B15O33(OH)3

2019 ◽  
Vol 74 (4) ◽  
pp. 357-363
Author(s):  
Daniela Vitzthum ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Temperature ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
Mixed Cation ◽  
High Pressure High Temperature ◽  
Pressure Synthesis

AbstractThe mixed cation triel borate Ga4In4B15O33(OH)3 was synthesized in a Walker-type multianvil apparatus at high-pressure/high-temperature conditions of 12.5 GPa and 1300°C. Although the product could not be reproduced in further experiments, its crystal structure could be reliably determined via single-crystal X-ray diffraction data. Ga4In4B15O33(OH)3 crystallizes in the tetragonal space group I41/a (origin choice 2) with the lattice parameters a = 11.382(2), c = 15.244(2) Å, and V = 1974.9(4) Å3. The structure of the quaternary triel borate consists of a complex network of BO4 tetrahedra, edge-sharing InO6 octahedra in dinuclear units, and very dense edge-sharing GaO6 octahedra in tetranuclear units.

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