A significant improvement in material of foam

Journal of Alloys and Compounds (Impact Factor: 3). 10/2013; 573:128–132. DOI: 10.1016/j.jallcom.2013.04.023


In investigation of different materials for electrodes used in electrolysers for hydrogen production, nickel foam shows wide interests in hydrogen scientific community. This paper brings novel results of performed experiments on pure nickel foam and nickel foam silver coated. The electrochemical behavior of chosen material in high concentrated alkaline media was studied using potentiostatic and potentiodynamic DC and AC electrochemical methods: linear polarization, electrochemical impedance spectroscopy. It was shown that using silver coatings enable higher hydrogen generation. There is defined linear region of the hydrogen production with evidence that an increasing of the electrodes overvoltage decreases the resistance to the charge transfer.

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Available from: Ankica Đukić, Dec 11, 2014
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    • "Zhao). 1 Current address: School of Materials Science and Engineering, Central South University, Changsha 410083, China. Contents lists available at ScienceDirect Materials Chemistry and Physics 19,710 cm 2 /g [9] "
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    ABSTRACT: Nickel catalysts were characterized for the hydrogen evolution reaction (HER) using rotating disk electrode (RDE) and electrochemical impedance spectroscopy (EIS). The theoretical Levich slope was calculated on the basis of the HER mechanism in alkaline solution. Kinetic and thermodynamic parameters of the reaction were obtained for fresh polished nickel electrode (Nif), and for nickel after a quick chronoamperometric aging procedure (Nipc). Koutecky-Levich analysis indicated that the rate determining step on Nif is the one-electron Volmer reaction, while for Nipc decreases from one to 0.68 and exhibits a strong temperature dependence. A loss of catalytic activity, corresponding to an increase of 0.3 V of the HER onset potential, was observed after aging. Furthermore, from the EIS-Tafel analysis we concluded that the H adsorption changes from a Langmuir type for Nif, to a Temkin type for Nipc.
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