Study on the activation methods for enhancing the performance of anion exchange membrane water electrolyzer using nickel-molybdenum catalyst for hydrogen evolution reaction

Abstract

Numerous investigations are currently underway pertaining to hydrogen as a potential substitute for fossil fuels, serving as an efficient medium for energy storage. Hydrogen exhibits a high energy density per unit mass, enabling surplus electrical energy generated from intermittent renewable sources to be converted into chemical energy and stored for on-demand utilization across diverse locations. Among the various methodologies for hydrogen production, employing the water electrolysis technique proves advantageous due to its minimal environmental impact, as only oxygen and hydrogen are generated by utilizing water as a reactant. Nevertheless, the process of water dissociation necessitates a certain amount of energy input, given its thermodynamically unfavorable nature, and thus, the fundamental objective of the hydrogen economy revolves around minimizing the energy requirements associated with this process. By employing an active catalyst with reduced activation energy, the energy expenditure for water decomposition can be effectively minimized. In this particular study, nickel-molybdenum alloy catalyst, active in aqueous electrolytes and facilitated by an anion exchange membrane, was synthesized and evaluated. Notably, the catalyst's activity was enhanced through a pre-reaction activation method within the membrane electrode assembly.