Electrochemical Lattice Engineering of Bismuthene for Selective Glycine Synthesis

Glycine plays a crucial role in various industrial and daily applications. However, traditional synthesis methods are often associated with high toxicity, energy intensity, and inefficiency. This study introduces an efficient and eco-friendly method for synthesizing glycine via the reductive coupling of oxalic acid and nitrate using a Bi metal catalyst, enhanced by lattice strain from Bi and oxide composites undergoing electrochemical transformation. At an applied potential of −0.76 V versus the reversible hydrogen electrode (RHE), the Bi catalyst achieves an impressive glycine Faradaic efficiency (FE) of 79.1%, yielding a record concentration of 0.17 m, substantially higher than conventional Bi-based systems. Furthermore, the introduction of glycolaldehyde and hydroxylamine as reactants raise the glycine FE to 91.3% with a production rate of 2433.3 µmol h⁻¹ under identical conditions. Electrochemical analysis and theoretical calculations demonstrate that lattice expansion notably boosts glycine synthesis by facilitating NH₂OH formation and promoting the efficient reduction of oxime intermediates. These results underscore the significance of lattice engineering in enhancing active site performance and accelerating reaction kinetics, offering a sustainable and efficient alternative to traditional glycine synthesis methods.