Lignin-derived carbon nanosheets boost electrochemical reductive amination of pyruvate to alanine

Shunhan Jia; Xingxing Tan; Limin Wu; Ziwei Zhao; Xinning Song; Jiaqi Feng; Libing Zhang; Xiaodong Ma; Zhanrong Zhang; Xiaofu Sun; Buxing Han

doi:10.1016/j.isci.2023.107776

Lignin-derived carbon nanosheets boost electrochemical reductive amination of pyruvate to alanine

iScience. 2023 Aug 29;26(10):107776. doi: 10.1016/j.isci.2023.107776. eCollection 2023 Oct 20.

Authors

Shunhan Jia^{1

2}, Xingxing Tan¹, Limin Wu^{1

2}, Ziwei Zhao^{1

2}, Xinning Song^{1

2}, Jiaqi Feng¹, Libing Zhang^{1

2}, Xiaodong Ma¹, Zhanrong Zhang^{1

2}, Xiaofu Sun^{1

2}, Buxing Han^{1

2

3}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences, Key Laboratory of Colloid and Interface and Thermodynamics, Center for Carbon Neutral Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
² School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
³ Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.

Abstract

Efficient and sustainable amino acid synthesis is essential for industrial applications. Electrocatalytic reductive amination has emerged as a promising method, but challenges such as undesired side reactions and low efficiency persist. Herein, we demonstrated a lignin-derived catalyst for alanine synthesis. Carbon nanosheets (CNSs) were synthesized from lignin via a template-assisted method and doped with nitrogen and sulfur to boost reductive amination and suppress side reactions. The resulting N,S-co-doped carbon nanosheets (NS-CNSs) exhibited outstanding electrochemical performance. It achieved a maximum alanine Faradaic efficiency of 79.5%, and a yield exceeding 1,199 μmol h^-1 cm^-2 on NS-CNS, with a selectivity above 99.9%. NS-CNS showed excellent durability during long-term electrolysis. Kinetic studies including control experiments and theoretical calculations provided further insights into the reaction pathway. Moreover, NS-CNS catalysts demonstrated potential in upgrading real-world polylactic acid plastic waste, yielding value-added alanine with a selectivity over 75%.

Keywords: Applied chemistry; Electrochemical materials science; Nanoelectrochemistry.