The impact of mechanical vibration at cathode on hydrogen yields in water electrolysis

Abstract

This study investigates the utilization of mechanical vibration to enhance the hydrogen evolution reaction (HER) in electrolysis processes. By varying the force magnitude and frequency of mechanical vibration, significant improvements in HER efficiency were observed. Specifically, the mechanical vibration-assisted electrolysis with a hitting frequency of 3 hits per second and 157.2698 Kg. m−2 hitting force improved the HER current density by 128 % compared to untreated water electrolysis. Linear sweep voltammetry (LSV) data for the graphite electrode revealed a distinct reduction peak at 1 V, indicating a favorable electrochemical reduction reaction influenced by mechanical vibration. The frequency of mechanical vibration significantly impacted the LSV response, with variations in current values across different conditions. Mechanistically, mechanical vibration disrupted intermolecular forces, facilitating better electrode-bubble interactions and accelerating reaction kinetics. Additionally, changes in pH levels induced by mechanical vibration further enhanced HER efficiency. These results suggest that integrating mechanical vibration into electrolysis systems significantly improves HER performance, contributing to the advancement of more efficient and sustainable hydrogen production technologies, which are crucial for achieving net-zero emission targets.