Chromium-Doped Nickel Oxide and Nickel Nitride Mediate Selective Electrocatalytic Oxidation of Sterol Intermediates Coupled with H2 Evolution.

Abstract

Replacing the OER with the thermodynamically favorable electrooxidation of organics is considered a promising approach for the simultaneous production of H2 and high-value chemicals. However, exploring and optimizing efficient electrocatalystsremains a challenge for large-scale production of high value-added steroid carbonyl and H2. Herein, Cr-NiO/GF and Cr-Ni3N/GF electrocatalysts were designed as anode and cathode for the production of steroid carbonyls and hydrogen, respectively. The cooperative Cr-NiO and ACT (4-acetamido-TEMPO) electrocatalyst can be extended to the electrooxidation of a series of steroid alcohols to the corresponding aldehydes. Additionally, Cr-Ni3N displays superior electrocatalytic activity for HER, with a low overpotential of 35 mV to deliver 10 mA cm-2. Furthermore, the system coupled with anodic electrooxidation of sterol and cathodic HER exhibited excellent performance with high space-time yield of 48.85 kg/(m3·h) for steroid carbonyl and 1.82 L/h for H2 generation in a two-layer stacked flow cell. DFT calculations indicated that Cr doping effectively stabilizes ACT on the NiO surface, and ACTH molecule could be captured via the ketonic oxygen interaction with Cr, resulting in excellent electrocatalytic activity. This work develops a novel approach to the rational design of efficient electrocatalysts for the simultaneous production of H2 and large-scale high added pharmaceutical carbonyl intermediates.