Energy saving in electrolytic hydrogen production using Co–Cr activation – Part I

The manuscript presents a report on the improved efficiency of alkaline electrolytic production of hydrogen by in situ adding directly into the electrolyte during the electrolytic process, cobalt and chrome based ionic activators. During electrolysis process the ionic activators deposit on the surface of the Ni cathode electrode and form an active, porous structure of high surface area.This simple process of adding in situ activating compounds directly into electrolyser is reducing the energy requirements per mass unit of hydrogen produced for about 15%, compared to non-activated system, for a number of current densities in a wide temperature range. Energy saving is higher at higher temperatures and on higher current densities. Structural and morphological characteristic of deposit formed on the cathode during the electrolytic process after in situ addition of activators, reveal interesting electrode surface pattern with highly developed surface area and uniform distribution of the pores. Obtained deposit also exhibit a long term stability.

► Improved efficiency of alkaline electrolytic production of hydrogen. ► In situ adding of cobalt and chrome based activators during the electrolytic process. ► Reduced energy requirements per mass unit of hydrogen produced for about 15%, compared to non-activated system. ► Interesting electrode surface pattern with highly developed surface area and uniform distribution of the pores.