Managing the Catalyst Energy Landscape: Continuous Fermi‐Level Tuning Eliminates the Overpotential Penalty in Organic Electrooxidation

ABSTRACT The energy efficiency of electrolytic hydrogen production is hampered by substantial anode overpotentials. While anodic organic oxidation is thermodynamically favorable, its practical potential is offset by high operational overpotentials, the origin of which remains unclear as static catalyst models fail to capture dynamic evolution. Here, by contrasting formaldehyde oxidation reaction (FOR) on stable Au versus reconstructing Ni(OH) 2 /NiOOH as a model system, we uncover a decisive mechanistic divergence: a 1.2 V higher onset potential on Ni(OH) 2 despite similar kinetics, ruling out molecular kinetics as the dominant cause. In situ spectroscopy and theoretical calculations reveal that on stable Au, with continuous Fermi‐level tuning, the molecular reaction barrier is the dominant factor governing overpotential. Conversely, on Ni(OH) 2 , electro‐triggered reconstruction forces a discontinuous Fermi‐level jump (from −4.95 eV to −7.4 eV), generating an energy‐excess catalytic state, which enables spontaneous and kinetically facile organic oxidation. This dominance of reconstruction energy ( Q R ) over molecular conversion energy ( Q M ) fundamentally governs catalytic efficiency, establishing Q R minimization as a key design principle for high‐performance catalysts.