Electrosynthesis of Glycine From Nitrate and Glyoxylic Acid Over a Bi2S3 Nanosheets-Based Catalyst.

Abstract

The green and efficient synthesis of amino acids is of great importance to both life science and the chemical industry. Electrocatalytic C─N coupling, driven by renewable electricity under mild conditions, offers a sustainable route for converting simple feedstocks into value-added nitrogen-containing compounds and thus provides a promising strategy for glycine production. Bismuth-based catalysts are commonly used in the electrosynthesis of amino acids. Herein, we report a Bi2S3 nanosheet-based catalyst for glycine electrosynthesis under acidic conditions, achieving 67.5% Faradaic efficiency (FE) and a yield rate of 0.51 mmol h-1 cm-2 at 200 mA cm-2. Operando Raman and attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) identify catalyst reconstruction and a tandem mechanism mediated by NH2OH and oxime intermediates. Combined with the control sulfurization experiment on Bi, we found that sulfur incorporation can modulate the product selectivity, possibly by influencing the subsequent hydrogenation of the oxime intermediate to glycine.