Rational Design of Ni3+‐Rich Nickel Nitride Enables Paired Electrooxidation of Sterol and Hydrogen Evolution in a Flow Electrolyzer

ABSTRACT Electrooxidation of sterols is recognized as a promising approach for synthesizing value‐added steroid hormone pharmaceuticals. However, enhancing current density while delivering market‐required steroidal carbonyl products with high selectivity remains a significant challenge. Herein, we report a rational design of Ni3+‐rich active sites on nickel nitride (Ni3N) nanosheets via Pd‐induced electronic modulation, which is utilized for sterol oxidation coupled with hydrogen evolution reaction (HER). Experimental and theoretical analyses demonstrated that the strong electron‐withdrawing capability of Pd acts as an “electron pump,” accelerating the formation of high‐valent Ni3+ active centers by attracting electrons from Ni3N to Pd, facilitating the adsorption and activation of N‐(1‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐4‐yl)acetamide (ACTH) during the oxidation process, thereby enhancing catalytic activity. The Pd‐Ni3N composite as a bifunctional electrocatalyst for producing carbonyl product 1b (19‐Hydroxy‐4‐androstene‐3,17‐dione) and H2 concurrently at an industrial‐scale current of 5 A in a large flow electrolyzer, achieving productivities of 70.9 mmol/h for 1b (with 99% selectivity) and 93.1 mmol/h for H2. This work provides a novel strategy for the electrosynthesis of valuable steroid intermediates alongside H2 production.