Electrifying Adipic Acid Production: Copper-Promoted Oxidation and C-C Cleavage of Cyclohexanol

Adipic acid is a central platform molecule for the polymer industry. Production of adipic acid with electroreforming technology is more sustainable compared to the thermochemical synthesis route. We discovered that incorporation of Cu²⁺ into a Ni hydroxide lattice significantly improved the electrocatalytic oxidation of cyclohexanol into adipate with a high yield (84 %) and selectivity (87 %). This Cu promotion effect serves as a mechanistic probe that can be combined with product analysis, steady-state kinetics, and in situ spectroscopy. A two-electron oxidation into cyclohexanone first occurs, followed by consecutive hydroxylation and C-C cleavage before dione formation. The central role of Cu²⁺ is to weaken the interaction between the NiOOH and surface-adsorbed O-centered radical that facilitates subsequent C-C cleavage. This enables a highly efficient two-electrode system capable of electroreforming KA oil into adipate and pure H₂ .