ABSTRACT
Against the background of escalating global electronic waste (e-waste) and its rich reservoir of elements, this research addresses the exploitation of precious metals from discarded CPUs for potential applications in hydrogen production. The study systematically explores the influence of varied CPU sample preparation techniques on the formation of an electrode's catalytic layer and the kinetics of the hydrogen evolution reaction (HER) in alkaline media. Four distinct e-waste samples, each subjected to different preparation protocols, were employed as sources in electrodeposition baths. The electrocatalytic efficiency of the resulting electrodeposited cathodes was evaluated, with the AR-CPU-1.4M electrode demonstrating superior properties. Morphological insights from SEM, coupled with elemental data from EDS and ICP analyses, revealed the intricate relationship between sample preparation, electrode characteristics, and HER kinetics. Notably, gold deposits and a prominent copper concentration emerged as defining attributes of our findings. This research underscores the potential of e-waste-derived metals, particularly in hydrogen production, providing an avenue for sustainable metal recovery and utilization.
ABSTRACT
Green hydrogen produced by alkaline electrolysis is a promising solution to address the world's increasing energy demand while mitigating greenhouse gas emissions. However, the efficient and cost-effective production of green hydrogen via alkaline electrolysis requires improvements. This paper presents an in situ activation process that simplifies the alkaline electrolysis technology while enhancing the catalytic activity of electrodes for the hydrogen evolution reaction. The aim of this research is to enhance the energy efficiency of alkaline electrolysis and decrease the energy consumption for hydrogen production. To achieve this goal, ionic activators comprising Ni, Zn, and Mo were incorporated into the standard electrolyte solution. Our results demonstrate that the anticipated improvement in the catalytic activity of the d-metal combination, surpassing even that of precious metals, has been successfully attained. As a result, a 20% reduction in energy consumption (REC) for the hydrogen produced has been observed. The catalytic activity of the added activators for the hydrogen evolution reaction was discussed by analyzing the mechanism of the reaction via Tafel analysis and EIS techniques. These findings offer a promising approach to improve alkaline electrolysis and enhance the production of green hydrogen.
