Piezopotential‐Driven Nitrogen Reduction for Sustainable Ammonia Synthesis via Metal–Piezoelectric Interfacial Coupling

Abstract

ABSTRACT Ambient ammonia synthesis remains highly challenging due to the inertness of N 2 and inefficient charge separation and interfacial reaction kinetics in current piezocatalytic systems. Herein, we report a metal–piezoelectric strategy by engineering amorphous Ru‐coated ZnO nanorods to enable highly efficient piezocatalytic nitrogen reduction. The introduction of an optimized amorphous Ru‐coated surface induces strong interfacial charge redistribution and establishes a built‐in electric field, which synergistically enhances piezoelectric polarization and carrier dynamics. As a result, the optimized ZnO‐NRs/10Ru exhibits a dramatically prolonged carrier lifetime (18 ns, an approximately ninefold increase) and the strongest piezoresponse among all samples. Piezo‐induced charge separation generates reductive • H species that may facilitate the hydrogenation of adsorbed nitrogen species, accompanied by • OH formation through hole‐mediated water oxidation. Under purely mechanical stimulation, ZnO‐NRs/10Ru achieves an ammonia yield of 2007.06 µmol g cat −1 L −1 h −1 , nearly twice that of pristine ZnO, with excellent structural stability and isotope‐confirmed nitrogen origin. Finite‐element simulations further demonstrate that the Ru‐coated surface optimizes internal piezopotential distribution while maintaining efficient charge transfer across the ZnO/Ru interface. This work provides a general strategy for metal‐modified piezoelectric catalysts toward sustainable ammonia synthesis and energy conversion applications.