Comparative analysis of in-situ ionic activators for increased energy efficiency process in alkaline electrolysers

Abstract

Electrodeposition of selected d-metals by in-situ electrodeposition as a method for improvement of electrocatalytic activity of conventional electrodes for alkaline hydrogen evolution has been attracting the attention of researchers for about two decades. The modification of metal electrodes by ionic activators as a combination of two (binary systems) or three (ternary systems) d-metal complexes added in electrolytic solution were represented in many studies. Better catalytic performances and higher energy efficiency compared to the common electrodes is provided by a number of affordable and inexpensive solutions resulting from this research. Based on the combinations of selected d-metal complexes added in-situ to the electrolyte during electrolysis, this work provides a systematic overview of the binary and ternary systems of ionic activators, that contribute to energy savings in alkaline electrolysers, with the particular attention paid to the discussion of similarities and universal principles. Theoretical background and the fundamental properties that lay beyond the observed improvements of electrode performance upon activation by ionic activators is also represented.