Biomimetic Elastic Single‐Atom Protrusions Enhance Ammonia Electrosynthesis

Abstract Electrocatalytic nitrogen (N 2 ) reduction reaction (eNRR) is a promising route for sustainable ammonia (NH 3 ) generation, but the eNRR efficiency is dramatically impeded by sluggish reaction kinetics. Herein, inspired by the dynamic extension‐contraction of sea anemone tentacles in response to environmental changes, we propose a biomimetic elastic Mo single‐atom protrusion on vanadium oxide support (pSA Mo/VOH) electrocatalyst featuring a symmetry‐breaking Mo site and an elastic Mo−O 4 pyramid for efficient eNRR. In situ spectroscopy and theoretical calculations reveal that the protruding Mo‐induced symmetry‐breaking structure optimizes the d‐electron filling of Mo, enhancing the back‐donation to the π* antibonding orbital, effectively polarizing the N≡N bond and reducing the barrier from *N 2 to *N 2 H. Notably, the elastic Mo−O 4 pyramidal structure of pSA Mo provides a dynamic Mo−O microenvironment during continuous eNRR processes. This optimizes the electronic structure of the Mo sites based on different reaction intermediates, enhancing the adsorption of various N intermediates and maintaining low barriers throughout the six‐step hydrogenation process. Consequently, the elastic pSA Mo/VOH exhibits an excellent NH 3 yield rate of 50.71±1.12 μg h −1 mg −1 and a Faradaic efficiency of 35.38±1.03 %, outperforming most electrocatalysts.