NADH Mimic‐Decorated Coordination Capsules for Biomimetic Capture of NO and Electrocatalytic Reduction to NH ₃

Abstract Sustainable conversion of NO offers a promising technology for artificial nitrogen cycle, but faces challenges in integrating electrocatalysis with NO capture. Herein, a biomimetic NO capture‐activation‐conversion strategy was firstly formulated by encapsulating N‐acetylcysteine ( NAC ) within a nicotinamide adenine dinucleotide (NADH) mimic‐containing coordination capsule, enabling efficiently NH 3 electrosynthesis. The installed NADH mimics onto the capsule interacted with the highly reactive NO‐adduct generated from NAC within the microenvironment akin to the pocket of enzyme, facilitating intramolecular hydride transfer of the substrate‐involving clathrate, accompanied by the formation of oxidated NAD + mimics. Subsequently, the cobalt‐based coordination capsule consecutively reserved e − from cathode while donating 2 e − to the NAD + mimic simultaneously for active cofactor recovered and recycle. This coordination capsule‐mediated biomimetic system exhibited enzymatic kinetics following the Michaelis–Menten mechanism in the electrochemical NO reduction and realized almost 100% Faraday efficiency at potentials below −0.2 V RHE with a substantial NH 3 yield rate of 121.6 µmol·h −1 ·cm −2 at −0.3 V RHE , ranking among the optimal electrocatalytic NO performance ever achieved, offering an attractive avenue toward renewable electricity‐driven nitrogen fixation exploiting bioinspired artificial catalyst.