Effect of Operating Temperature on Ni–Fe Alloy Nanostructured Electrodes for Alkaline Electrolyzer

Abstract

Herein, the effect of operating temperature on alkaline electrolytic cells for hydrogen generation using nanostructured electrodes is studied. Nanostructured nickel-iron alloy electrodes are obtained by electrosynthesis in a template. These electrodes are characterized by a nanowire-like structure with a high active surface area and consequently a higher catalytic activity than non-nanostructured materials. The chemical and morphological features of nanostructured electrodes are evaluated by energy-dispersive spectroscopy, X-ray diffraction, and scanning electron microscopy analyses. The electrochemical behavior of the nanostructured electrodes is studied through different tests in alkaline solutions. Tests are performed at different temperatures, 25, 40, and 60 degrees C, to evaluate the performance in terms of hydrogen and oxygen production and to verify the medium-term stability under galvanostatic conditions. The electrodes demonstrate good stability over time without evident signs of performance decay. The performance of a homemade electrolyzer with nanostructured electrodes is also studied at different temperatures and under industrial operation conditions for 600 h. The environmental impacts through the application of life cycle assessment methodology are also evaluated.