Biomimetic Elastic Single‐Atom Protrusions Enhance Ammonia Electrosynthesis

Electrocatalytic nitrogen (N2) reduction reaction (eNRR) is a promising route for sustainable ammonia (NH3) generation, but the eNRR efficiency is dramatically impeded by the 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−O4 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 *N2 to *N2H. Notably, the elastic Mo−O4 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 NH3 yield rate of 50.71 ± 1.12 μg h−1 mg−1 and a Faradaic efficiency of 35.38 ± 1.03%, outperforming most electrocatalysts.