Selective Glycine Electrosynthesis via C‐N Coupling Enabled by Synergistic Mott–Schottky Heterojunction and Oxygen Vacancies
Abstract
ABSTRACT Glycine, an indispensable amino acid essential for diverse biological processes, remains challenging to synthesize directly via electrosynthesis from simple carbon and nitrogen precursors. Herein, we report a highly efficient electrochemical route for glycine production through the reductive coupling of oxalic acid (H 2 C 2 O 4 ) with hydroxylamine (NH 2 OH) or nitrate (NO 3 − ) over a Mott–Schottky Sn/SnO 2 heterojunction catalyst enriched with oxygen vacancies. When employing H 2 C 2 O 4 and NH 2 OH as feedstocks, a remarkable Faradaic efficiency (FE) of 91.6% for glycine is achieved at −0.7 V versus RHE, alongside a high yield of 135 mmol g cat. −1 h −1 . To the best of our knowledge, this represents one of the best performances ever reported in this system. The catalyst also shows strong substrate versatility, enabling efficient glycine formation when NO 3 − (in situ reduced to NH 2 OH) couples with glyoxylic acid or H 2 C 2 O 4 . Mechanistic studies indicate that the Mott–Schottky heterojunction significantly promotes the co‐adsorption of H 2 C 2 O 4 and NH 2 OH, while oxygen vacancies facilitate the hydrogenation of oxime intermediates to glycine. This study highlights the profound synergistic interplay between Mott–Schottky heterojunctions and oxygen vacancy defects in precisely modulating active sites and accelerating reaction kinetics, thereby offering a sustainable strategy for the green electrosynthesis of amino acids.
Article Details
Authors (15)
Guangkuo Xu
Chengyuan Dong
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Xiangcheng Cai
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Junhua Kuang
Tianwei Xue
College of Energy, College of Chemistry and Chemical Engineering
Yuyu Guo
State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University
Yanyin Wu
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Ruiqing Li
State Key Laboratory of Functional Crystals and Devices
Zeyu Shao
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Tongxin Qiao
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Wenli Hao
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Longzhao Xu
State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian China
Shuliang Yang
Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
Jun Li
Li Peng