Phosphorus‐Modulated Cobalt Nanosheets with Confined Metal Defects for Enhanced Kinetics in Nitrite‐Glycerol Co‐Electrolysis

Abstract Exploring advanced electrocatalysts for the paired electrolysis of the nitrite reduction reaction (NO₂RR) and glycerol oxidation reaction (GOR) is of significance for the co‐production of value‐added chemicals, but remains a great challenge. Herein, a novel phosphorus‐modulated cobalt nanosheet with low‐coordination metallic sites (P₃‐Co) is developed as an advanced electrocatalyst for efficient nitrite‐glycerol co‐electrolysis. The membrane electrode assembled NO₂RR‖GOR electrolyzer realizes promising operation performance with high Faradaic efficiencies and yields of NH₃ (98.2%, 29.3 mg h⁻¹ cm⁻²) and formate (93.4%, 85.7 mg h⁻¹ cm⁻²) at 1.5 V, as well as superior catalytic stability over a long‐term electrolysis of 300 h at 100 mA cm⁻². The in situ characterizations and theoretical calculations are employed to reveal the origin of intrinsic high activity of P₃‐Co, suggesting that the metal Co defects and P‐modulation are beneficial to optimizing the electronic structure and the adsorption/activation barriers of N‐containing intermediates for the accelerated conversion kinetics of both GOR and NO₂RR. This work offers guidance for exploiting highly‐active electrocatalysts for the generation of high‐value‐added products.