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Title: Electrodeposited NiCo/Cu Superlattices

Abstract

NiCo/Cu superlattices were electrodeposited on polycrystalline Cu substrates from a single electrolyte under potentiostatic control. The X-ray diffraction (XRD) patterns showed that NiCo/Cu superlattices have the same crystal structure and texture as in their substrates. The films exhibited giant magnetoresistance (GMR) or anisotropic magnetoresistance (AMR), depending on the Cu layer thicknesses.

Authors:
;  [1]
  1. Department of Physics, Faculty of Science and Literature, University of Uludag, Goeruekle, Bursa (Turkey)
Publication Date:
OSTI Identifier:
21057232
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 899; Journal Issue: 1; Conference: 6. international conference of the Balkan Physical Union, Istanbul (Turkey), 22-26 Aug 2006; Other Information: DOI: 10.1063/1.2733385; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; COBALT ALLOYS; COPPER; CRYSTAL STRUCTURE; ELECTRODEPOSITION; ELECTROLYTES; FILMS; INTERFACES; LAYERS; MAGNETORESISTANCE; NICKEL ALLOYS; POLYCRYSTALS; SUBSTRATES; SUPERLATTICES; TEXTURE; THICKNESS; X-RAY DIFFRACTION

Citation Formats

Safak, M., and Alper, M.. Electrodeposited NiCo/Cu Superlattices. United States: N. p., 2007. Web. doi:10.1063/1.2733385.
Safak, M., & Alper, M.. Electrodeposited NiCo/Cu Superlattices. United States. doi:10.1063/1.2733385.
Safak, M., and Alper, M.. Mon . "Electrodeposited NiCo/Cu Superlattices". United States. doi:10.1063/1.2733385.
@article{osti_21057232,
title = {Electrodeposited NiCo/Cu Superlattices},
author = {Safak, M. and Alper, M.},
abstractNote = {NiCo/Cu superlattices were electrodeposited on polycrystalline Cu substrates from a single electrolyte under potentiostatic control. The X-ray diffraction (XRD) patterns showed that NiCo/Cu superlattices have the same crystal structure and texture as in their substrates. The films exhibited giant magnetoresistance (GMR) or anisotropic magnetoresistance (AMR), depending on the Cu layer thicknesses.},
doi = {10.1063/1.2733385},
journal = {AIP Conference Proceedings},
number = 1,
volume = 899,
place = {United States},
year = {Mon Apr 23 00:00:00 EDT 2007},
month = {Mon Apr 23 00:00:00 EDT 2007}
}
  • Highlights: • The novel NiCo–Zr coatings were prepared by electro-deposition. • Surface morphology, crystal structure, grain size and microstrain were examined. • Texture, residual stress and corrosion resistance were investigated. • Addition of Co increased the hardness and corrosion resistance of the coatings. - Abstract: In this study, the NiCo–Zr composite coatings were prepared from the electrolytes with different Co{sup 2+} concentrations by electrodeposition method. The effects of Co contents on the crystal structure, surface morphology, grain size, microstrain and residual stress were examined by X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX) andmore » atomic force microscope (AFM). The corrosion resistance of the composite coatings was also examined by the potentiodynamic polarization and electrochemical impedance (EIS) measurements. The results revealed that the crystal structures of the coatings were dependent on the Co contents and addition of Co content of 58 wt% resulted in the formation of hexagonal (hcp) Co. The increasing Co contents in the NiCo–Zr composite coatings resulted in the smoother and more compact surface, decreased the grain size and increased the microstrain. The micro-hardness and residual stress also increased with increasing Co contents. The addition of Co increased the corrosion resistance of the NiCo–Zr composite coatings compared with the Ni–Zr coating while the corrosion resistance of the NiCo–Zr composite coatings decreased as the Co contents increased.« less
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  • Graphical abstract: Mesoporous hydrangea macrophylla like NiCo{sub 2}O{sub 4} and NiCo{sub 2}S{sub 4} have been fabricated, which present excellent electrochemical performances as anode materials for Li-ion batteries. - Highlights: • Hierarchical NiCo{sub 2}O{sub 4} is successfully fabricated. • Hierarchical NiCo{sub 2}S{sub 4} is prepared via sulfide anion exchange. • The hierarchical NiCo{sub 2}O{sub 4} and NiCo{sub 2}S{sub 4} exhibit good electrochemical properties. - Abstract: In this work, hierarchical hydrangea macrophylla like NiCo{sub 2}O{sub 4} has been synthesized by solvothermal method followed by calcination treatment in air. By using Na{sub 2}S as sulfur source, the NiCo{sub 2}O{sub 4} is converted intomore » NiCo{sub 2}S{sub 4}. Such hierarchical NiCo{sub 2}O{sub 4} exhibits a high specific capacity and excellent cycling stability (928 mAh g{sup −1} at a current density of 100 mA g{sup −1} after 100 cycles). Even at high current density of 2000 mA g{sup −1}, the electrode still delivers a specific capacity of 371 mAh g{sup −1} after 50 cycles. When the NiCo{sub 2}S{sub 4} is used as anode materials for lithium-ion batteries, a high discharge capacity of 1204 mAh g{sup −1} can be achieved. Meanwhile, the NiCo{sub 2}S{sub 4} electrode displays good cycling stability and rate capability. The excellent electrochemical performances can be attributed to the unique porous structure, which can effectively reduce the diffusion length for lithium ions and electrons, and alleviate volume expansion during the charge-discharge processes.« less
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