Boosting high-current alkaline water electrolysis and carbon dioxide reduction with novel CuNiFe-based anodes

TL;DR

This paper introduces a novel CuNiFe-based anode for alkaline water electrolysis and CO2 reduction, demonstrating high activity, stability, and environmental benefits, suitable for scalable green hydrogen production.

Contribution

A scalable, high-performance CuNiFe anode fabricated via single-step electrodeposition, enhancing electrolysis efficiency and environmental sustainability.

Findings

Achieves <270 mV overpotential at 100 mA/cm²

Operates stably over 500 hours at 1 A/cm² in alkaline solution

Triples CO2 reduction current density and improves selectivity

Abstract

The transition to a green hydrogen economy demands robust, scalable, and sustainable anodes for alkaline water electrolysis operating at industrial current densities (>1 A/cm2). However, achieving high activity and long-term stability under such conditions remains a formidable challenge with conventional catalysts. Here, we report a novel trimetallic CuNiFe anode fabricated through a rapid, single-step electrodeposition process at room temperature without organic additives. The catalyst exhibits an exceptionally low overpotential of <270 mV at 100 mA cm(-2) and operates stably for over 500 hours at 1 A cm(-2) in 30 wt% KOH. In a practical anion exchange membrane water electrolyzer (AEM-WE), the CuNiFe anode enables a current density of 2.5 A cm(-2) at only 2.5 V, with a voltage efficiency of 66.8%. Beyond water splitting, this anode also significantly enhances CO2 electrolysis, tripling the CO2 reduction current density and steering selectivity toward valuable multi-carbon products when paired with commercial copper cathodes. A cradle-to-gate life cycle assessment confirms that the CuNiFe anode reduces the carbon footprint by an order of magnitude and decreases environmental impacts by 40-60% across multiple categories compared to benchmark IrRuO2. Our work establishes a scalable, high-performance, and environmentally benign anode technology, paving the way for cost-effective electrochemical production of green hydrogen and carbon-neutral chemicals.