Publication Type Journal Article
Title ELECTROCHEMICAL RESPONSE OF 70Co-30Ni HIGHLY BRANCHED 3D-DENDRITIC STRUCTURES FOR CHARGE STORAGE ELECTRODES
Authors T. M. Silva S Eugénio R.G. Duarte Maria J. Carmezim Maria F. Montemor
Groups CSSE
Journal ELECTROCHIMICA ACTA
Year 2015
Month June
Volume 167
Number
Pages 13-19
Abstract A 70Co-30Ni dendritic alloy was produced on stainless steel by pulse electrodeposition in the cathodic domain, and oxidized by potential cycling. X-ray diffraction (XRD) identified the presence of two phases and scanning electron microscopy (SEM) evidenced an open 3D highly branched dendritic morphology. After potential cycling in 1 M KOH, SEM and X-ray photoelectron spectroscopy (XPS) revealed, respectively, the presence of thin nanoplates, composed of Co and Ni oxi-hydroxides and hydroxides over the original dendritic film. Cyclic voltammetry tests showd the presence of redox peaks assigned to the oxidation and reduction of Ni and Co centres in the surface film. Charge/discharge measurements revealed capacity values of 121 mAh g(1) at 1 mA cm(2). The capacity retention under 8000 cycles was above 70\%, stating the good reversibility of these redox materials and its suitability to be used as charge storage electrodes. Electrochemical impedance spectroscopy (EIS) spectra, taken under different applied bias, showed that the capacitance increased when the electrode was fully oxidized and decreased when the electrode was reduced, reflecting different states-of-charge of the electrode. (C) 2015 Elsevier Ltd. All rights reserved.
DOI http://dx.doi.org/10.1016/j.electacta.2015.03.083
ISBN
Publisher PERGAMON-ELSEVIER SCIENCE LTD
Book Title
ISSN 0013-4686
EISSN 1873-3859
Conference Name
Bibtex ID ISI:000354053400002
Observations
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