Doping Mo Triggers Charge Distribution Optimization and P Vacancy of Ni2P@Ni12P5 Heterojunction for Industrial Electrocatalytic Production of Adipic Acid and H2

Synchronous electrosynthesis of value-added adipic acid (AA) and H2 is extremely crucial for carbon neutrality. However, accomplishing the preparation of AA and H2 at large current density with high selectivity is still challenging. Herein, a robust Mo-doped Ni2P@Ni12P5 heterojunction with more P vacancies on Ni foam is proposed for accomplishing simultaneous electrooxidation of cyclohexanol (CHAOR) to AA and hydrogen evolution reaction (HER) at large current density. Combined X-ray photoelectron spectroscopy, X-ray absorption fine structure, and electron spin resonance confirm that Mo incorporation induces the charge redistribution of Ni2P@Ni12P5, where Mo adjusts electrons from Ni to P, and triggers more P vacancies. Further experimental and theoretical investigations reveal that the d-band center is upshifted, optimizing adsorption energies of water and hydrogen on electron-rich P site for boosting HER activity. Besides, more Ni3+ generated from electron-deficient Ni induced by Mo, alongside more OH* triggered from more P vacancies concurrently promote CHA dehydrogenation and C─C bond cleavage, decreasing energy barrier of CHAOR. Consequently, a two-electrode flow electrolyzer achieves industrial current density (>230 mA cm-2) with 85.7% AA yield, 100% Faradaic efficiency of H2 production. This study showcases an industrial bifunctional electrocatalyst for AA and H2 production with high productivity.