Cu‐Sn Biphasic Alloy Heterostructure With <i>p‐d</i> Orbital Hybridization for Efficient Electrosynthesis of Amino Acids

The electrocatalytic conversion of NO_x species into amino acids is an attractive approach. However, significant challenges lie in the matching kinetics of C-N coupling and high selectivity for the target product. Herein, a Cu₃Sn/Cu₆Sn₅ biphasic alloy heterostructure (Cu-Sn BAH) with p-d orbital hybridization has been constructed by phase control engineering for enhanced amino acid electrosynthesis, delivering a remarkable glycine Faradaic efficiency of 80% and a selectivity of 93% at -0.8 V vs. RHE. Experimental and mechanistic studies reveal that the strong p-d orbital hybridization between d-block Cu and p-block Sn effectively modulates interfacial electronic structure between Cu₃Sn and Cu₆Sn₅ biphasic alloys, promoting the electron transfer and optimizing the adsorption of NO_3- and glyoxylic acid, and thus facilitating the generation of *NH₂OH with reduced energy barriers and subsequent oxime hydrogenation. This work offers a distinctive electrocatalyst design strategy for highly selective amino acid synthesis via orbital engineering and heterostructure construction, and also encourages the development of C-N coupling systems.