High‐Efficiency Electrochemical Nitrogen Fixation by Noble‐Metal‐Free Metallic Glasses

Abstract The electrocatalytic nitrogen reduction reaction (NRR) represents an energy‐efficient alternative to the traditional Haber‐Bosch process for industrial ammonia synthesis. However, the cleavage of the strong N≡N bond hinders the practical application of NRR. Herein, an innovative design strategy is proposed based on a Fe 76 Si 8 B 13 Nb 3 metallic glass (MG‐FeSiBNb) catalyst, featuring a unique amorphous structure with endogenous nanoscale compositional heterogeneity. This catalyst achieves an impressive ammonia yield rate of 92.1 µg h −1 mg −1 cat. in 0.1 m Na 2 SO 4 solution, surpassing most state‐of‐the‐art NRR electrocatalysts. Extended X‐ray absorption fine structure analysis reveals that MG‐FeSiBNb provides abundant unsaturated coordination sites, essential for effective N 2 adsorption. Furthermore, electronic structural characterizations and density functional theory calculations demonstrate that the incorporation of Si, B, and Nb atoms into the Fe‐based matrix precisely tailors the local electronic environment, effectively shifting the Fe d‐band center toward the Fermi level. This electronic modulation enhances electron transfer efficiency, thus promoting the hydrogenation of * NH 2 to * NH 3 . Additionally, the amorphous nature of MG‐FeSiBNb suppresses hydrogen adsorption by eliminating well‐defined crystal facets, thereby selectively mitigating the hydrogen evolution reaction and enhancing NRR selectivity. This work offers not only a high‐performing NRR catalyst but also a generalizable strategy for sustainable electrocatalysis beyond conventional crystalline systems.