Three-dimensional porous Ni film electrodeposited on Ni foam: High performance and low-cost catalytic electrode for H2O2 electrooxidation in KOH solution

A novel three-dimensional carbon- and binder-free porous Ni electrode is successfully prepared by electrodeposition of Ni microparticle assembly on Ni foam substrate using hydrogen bubbles as the template. Scanning electron microscopy and X-ray diffraction analyses are performed to characterize the morphology and structure. Electrochemical methods including cyclic voltammetry and chronoamperometry are used to examine the catalytic performance of electrode for H2O2 electrooxidation in KOH solution. Results reveal that the electrode exhibited high catalytic activity and good stability in the strong oxidizing and corrosive solution of H2O2 and KOH. The catalytic mechanism of H2O2 electrooxidation on the Ni electrode is discussed and Ni(OH)2 is believed to be the catalytic active species. The apparent activation energy of H2O2 electrooxidation on the Ni catalyst is found to be 21.2 kJ mol−1. A direct peroxide-peroxide fuel cell using the Ni/Ni-foam as the anode achieves a peak power density of 19.4 mW cm−2, higher than that reported in literatures. The electrode shows great promise as the anode of direct peroxide-peroxide fuel cell due to its low cost, high activity and stability.