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

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.

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

Surface Review and Letters ◽

10.1142/s0218625x15501115 ◽

2016 ◽

Vol 23 (02) ◽

pp. 1550111 ◽

Cited By ~ 3

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.

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Influence of HAP on the Morpho-Structural Properties and Corrosion Resistance of ZrO2-Based Composites for Biomedical Applications

Crystals ◽

10.3390/cryst11020202 ◽

2021 ◽

Vol 11 (2) ◽

pp. 202

Author(s):

Réka Barabás ◽

Carmen Ioana Fort ◽

Graziella Liana Turdean ◽

Liliana Bizo

Keyword(s):

Electrochemical Impedance ◽

Artificial Saliva ◽

Synergetic Effect ◽

Composite Layer ◽

Charge Transfer Resistance ◽

Processing Route ◽

Dental Alloys ◽

Metallic Electrode ◽

Transfer Resistance ◽

X Ray

In the present work, ZrO2-based composites were prepared by adding different amounts of antibacterial magnesium oxide and bioactive and biocompatible hydroxyapatite (HAP) to the inert zirconia. The composites were synthesized by the conventional ceramic processing route and morpho-structurally analyzed by X-ray powder diffraction (XRPD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Two metallic dental alloys (i.e., Ni–Cr and Co–Cr) coated with a chitosan (Chit) membrane containing the prepared composites were exposed to aerated artificial saliva solutions of different pHs (i.e., 4.3, 5, 6) and the corrosion resistances were investigated by electrochemical impedance spectroscopy technique. The obtained results using the two investigated metallic dental alloys shown quasi-similar anticorrosive properties, having quasi-similar charge transfer resistance, when coated with different ZrO2-based composites. This behavior could be explained by the synergetic effect between the diffusion process through the Chit-composite layer and the roughness of the metallic electrode surface.

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From Allergens to Battery Anodes: Nature-Inspired, Pollen Derived Carbon Architectures for Room- and Elevated- Temperature Li-ion Storage

Scientific Reports ◽

10.1038/srep20290 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 22

Author(s):

Jialiang Tang ◽

Vinodkumar Etacheri ◽

Vilas G. Pol

Keyword(s):

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

High Rate ◽

Energy Storage Devices ◽

Lithium Storage ◽

Transfer Resistance ◽

Carbonaceous Particles ◽

X Ray

Abstract The conversion of allergic pollen grains into carbon microstructures was carried out through a facile, one-step, solid-state pyrolysis process in an inert atmosphere. The as-prepared carbonaceous particles were further air activated at 300 °C and then evaluated as lithium ion battery anodes at room (25 °C) and elevated (50 °C) temperatures. The distinct morphologies of bee pollens and cattail pollens are resembled on the final architecture of produced carbons. Scanning Electron Microscopy images shows that activated bee pollen carbon (ABP) is comprised of spiky, brain-like and tiny spheres; while activated cattail pollen carbon (ACP) resembles deflated spheres. Structural analysis through X-ray diffraction and Raman spectroscopy confirmed their amorphous nature. X-ray photoelectron spectroscopy analysis of ABP and ACP confirmed that both samples contain high levels of oxygen and small amount of nitrogen contents. At C/10 rate, ACP electrode delivered high specific lithium storage reversible capacities (590 mAh/g at 50 °C and 382 mAh/g at 25 °C) and also exhibited excellent high rate capabilities. Through electrochemical impedance spectroscopy studies, improved performance of ACP is attributed to its lower charge transfer resistance than ABP. Current studies demonstrate that morphologically distinct renewable pollens could produce carbon architectures for anode applications in energy storage 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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Preparation and electrochemical characterization of PANI/MnCo2O4 nanocomposite as supercapacitor electrode material

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0423 ◽

2018 ◽

Vol 96 (5) ◽

pp. 477-483 ◽

Cited By ~ 3

Author(s):

Saeid Panahi ◽

Moosa Es’haghi

Keyword(s):

Specific Capacitance ◽

Surface Characterization ◽

Electrochemical Impedance ◽

Rate Capability ◽

Cycling Performance ◽

Charge Transfer Resistance ◽

X Ray Diffraction ◽

Supercapacitor Electrode ◽

Transfer Resistance

In this work, PANI/MnCo2O4 nanocomposite was prepared via in-situ chemical polymerization method. Materials synthesized were characterized by FTIR spectroscopy, X-ray diffraction, and scanning electron spectroscopy. In addition, surface characterization of samples such as specific surface area, pore volume, and pore size distribution was studied. Supercapacitor capability of materials was investigated in 1 mol L–1 Na2SO4 solution using cyclic voltammetry in different potential scan rates and electrochemical impedance spectroscopy (EIS). The specific capacitance of materials was calculated, and it was observed that the specific capacitance of PANI/MnCo2O4 nanocomposite was 185 F g−1, much larger than PANI. Moreover, the prepared nanocomposite exhibited better rate capability in scan rate of 100 mV s−1 with respect to PANI. The EIS experiments revealed that the nanocomposite has lower charge transfer resistance compared with pure PANI. Subsequently, it was shown that the nanocomposite cycling performance was superior to the PANI cycling performance.

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STUDY OF ZN-NI ALLOY COATINGSMODIFIED BY NANO-AL2O3 PARTICLES INCORPORATION

Acta Metallurgica Slovaca ◽

10.12776/ams.v22i3.706 ◽

2016 ◽

Vol 22 (3) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Malika Diafi ◽

Said Benramache ◽

Elhachmi Guettaf Temam ◽

Adaika Mohamed Lakhdar ◽

Brahim Gasmi

Keyword(s):

Electrochemical Impedance ◽

Research Work ◽

Charge Transfer Resistance ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Corrosion Properties ◽

Transfer Resistance ◽

Characterization Methods ◽

Ni Alloy ◽

Steel Substrates

AbstractThe aim of this research work was to codeposit nano-Al2O3 particles into Zn-Ni alloy coatings in order to improve some surface ,properties, the influence of the concentration of Al2O3 is the principal object in order to improve the corrosion resistance of the deposit, which has been made by electroplating on steel substrates previously treated, have been studied by several characterization methods, as the X-ray diffraction, measurement of micro hardness and scanning electron microscopy (SEM), protection against corrosion properties studied in a solution of 3% NaCl in the potentiodynamic polarization measurements (Tafel), electrochemical impedance spectroscopy (EIS) to the potential of corrosion free. The parameters that characterize the corrosion behavior can be determined from the plots and Nyquist plots and chronopotentiometry. Trends of increasing the charge transfer resistance and the decrease of capacitance values. XRD and SEM results and identify any coatings Zn-Ni and Zn-Ni-Al2O3 alloy composition have similar phase ( γ-phase structure) and the addition of Al2O3 in the Zn-Ni matrix increases the microhardness, and we note the maximum hardness is obtained for 50 g/L Al2O3.

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Electrochemical behavior of hydrogen precipitated Zircaloy-4

Modern Physics Letters B ◽

10.1142/s0217984915502000 ◽

2015 ◽

Vol 29 (32) ◽

pp. 1550200 ◽

Cited By ~ 6

Author(s):

Mohsin Rafique ◽

Naveed Afzal ◽

K. M. Deen ◽

Yong-Soo Kim

Keyword(s):

Hydrogen Concentration ◽

Electrochemical Behavior ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

X Ray Diffraction ◽

Transfer Resistance ◽

Corrosion Kinetics ◽

Before And After ◽

Potentiodynamic Anodic Polarization ◽

Kinetics Of

This work investigates the hydrogen precipitation effects on the electrochemical behavior of Zircaloy-4 in acidic saline media. The specimens of Zircaloy-4 were hydrogen charged at 200, 400 and 600 ppm concentrations for 30 min at 400[Formula: see text]C. X-ray diffraction (XRD) studies confirmed the formation of delta hydrides in the material. Scanning electron microscopy (SEM) results also indicated the presence of elongated hydrides whose density and thickness increased with the increase of hydrogen concentration in the alloy. The corrosion kinetics of the specimens were explored before and after hydrogen precipitation using potentiodynamic anodic polarization (PAP) and electrochemical impedance spectroscopy (EIS) techniques. The results showed that hydrogen precipitation shifts the corrosion potential towards more positive and thus improves the corrosion resistance of the alloy. The charge transfer resistance [Formula: see text] of the alloy was found to increase with increasing hydrogen concentration. This indicates an increased polarization tendency of the Zircaloy-4 surface with a limited dissolution tendency in the presence of delta hydrides.

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

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2015.11197 ◽

2015 ◽

Vol 15 (10) ◽

pp. 8042-8047 ◽

Cited By ~ 5

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.

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Study of solvent effect on structural and photoconductive behavior of ternary chalcogenides InBiS3-In2S3-Bi2S3 composite thin films deposited via AACVD

Main Group Metal Chemistry ◽

10.1515/mgmc-2019-0011 ◽

2019 ◽

Vol 42 (1) ◽

pp. 102-112 ◽

Cited By ~ 1

Author(s):

Umar Daraz ◽

Tariq Mahmood Ansari ◽

Shafique Ahmad Arain ◽

Muhammad Adil Mansoor ◽

Muhammad Mazhar

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Visible Region ◽

Chloroform Solution ◽

Photocurrent Density ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

X Ray ◽

Wide Range

Abstract In the present work ternary composite InBiS3-In2S3-Bi2S3 (IBS) thin films are developed using a homogeneous mixture of precursors [Bi(S2CN(C2H5)2)3]2 (1) and [In(S2CNCy2)3]‧2py (2), separately in toluene and chloroform solutions at 500°C under an inert atmosphere of argon gas via aerosol assisted chemical vapor deposition (AACVD) technique. The phase purity, chemical composition and morphological study of both the films deposited from toluene and chloroform solutions are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Field emission scanning electron microscopy (FESEM). The surface morphology showed rod like structure of the films developed from toluene while the films grown from chloroform solution give flake like shapes. The UV-visible spectroscopy explicated that the thin films developed from toluene and chloroform solutions show wide range absorption in whole visible region. Linear Scan voltammetry results show that both the films give negligible dark current, however, the films fabricated from toluene solution give a sharp steep curve with maximum photocurrent density of 2.3 mA‧cm-2 at 0.75 V vs Ag/AgCl/3M KCl using 0.05 M sodium sulphide solution under AM 1.5 G illumination (100 mW‧cm-2), while the film grown from chloroform generates a photocurrent density of 2.1 mA‧cm-2 under similar conditions. The LSV outcomes are further supported by electrochemical impedance spectroscopy (EIS) that gives charge transfer resistance (Rct) value of 8,571 Ω for the films developed from toluene as compared to films fabricated from chloroform with Rct value of 12,476 Ω.

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