Industrial‐scale Aldehydes Electrification Via Localized Hydrogen‐affinity Engineering

Electrifying aldehydes into high‐value chemicals presents a sustainable solution for environmental remediation, resource recovery and upgrade, yet its practical implementation has been limited by inefficient electrodes. Here, we develop a computation‐guided strategy—localized hydrogen‐affinity engineering—to synthesize heteroatom‐decorated Cu hydrogenase for aldehydes electrification. Remarkably, the as‐prepared Rh‐decorated Cu hydrogenase (Rh 1 Cu‐Hase) achieves a remarkable Faraday efficiency of >99.3% for formaldehyde conversion at an ultrahigh current density of 500 mA cm −2 with a minimal overpotential of 283 mV. A membrane‐free electrolyzer equipped with the Rh 1 Cu‐Hase operates stably for over 1200 h at 1000 mA cm −2 , continuously producing high‐purity potassium diformate (KDF) and hydrogen. Techno‐economic analysis reveals a significant $166.1/ton KDF revenue advantage over conventional methods. The paired dehydrogenation mechanism is proposed by a series of operando studies and theoretical calculations, unveiling that the Cu matrix facilitates aldehyde adsorption, while atomic Rh sites activate hydrogen, collectively reducing energy barriers for both C─H cleavage and H─H coupling. Furthermore, the universality of this strategy is demonstrated by its successful application in electrifying a broad range of industrially relevant aldehydes.