Energy, Vol.63, 216-224, 2013
Characterization of the porous Ni3Al-Mo electrodes during hydrogen generation from alkaline water electrolysis
Objective of this work is to investigate the electrocatalytic efficiency using cyclic voltammetry, cathodic polarization and impedance spectroscopy techniques of the porous Ni3Al-Mo electrodes obtained by reactive synthesis of Ni, Al and Mo elemental powders. The kinetic parameters are determined from electrochemical steady-state polarization and electrochemical impedance spectroscopy technology in 6 M KOH. The Tafel slopes are around 0.13 V dec(-1), and exchange current densities are close to 0.02 mA cm(-2). Moreover, the porous Ni3Al-Mo electrodes possess high stability during prolonged electrolysis. Results are presented to show Tafel slopes, exchange current densities, apparent energy of activation and stability of the catalysts. Results suggest the significant catalytic performance not only from the increase of the real surface area of electrodes, but also from the true catalytic effect. (C) 2013 Elsevier Ltd. All rights reserved.
Keywords:Hydrogen evolution reaction;Porous Ni3Al-Mo electrodes;Reactive synthesis;Powder metallurgy;Electrochemical;Impedance spectroscopy