Overcoming Energy-Scaling Barriers: Efficient Ammonia Electrosynthesis on High-Entropy Alloy Catalysts

Electrochemically converting nitrate (NO₃⁻) to value-added ammonia (NH₃) is a complex process involving an eight-electron transfer and numerous intermediates, presenting a significant challenge for optimization. A multi-elemental synergy strategy to regulate the local electronic structure at the atomic level is proposed, creating a broad adsorption energy landscape in high-entropy alloy (HEA) catalysts. This approach enables optimal adsorption and desorption of various intermediates, effectively overcoming energy-scaling limitations for efficient NH₃ electrosynthesis. The HEA catalyst achieved a high Faradaic efficiency of 94.5 ± 4.3% and a yield rate of 10.2 ± 0.5 mg h⁻¹ mg_cat⁻¹. It also demonstrated remarkable stability over 250 h in an integrated three-chamber device, coupling electrocatalysis with an ammonia recovery unit for continuous NH₃ collection. This work elucidates the catalytic mechanisms of multi-functional HEA systems and offers new perspectives for optimizing multi-step reactions by circumventing adsorption-energy scaling limitations.