Mercaptoimidazole‐Engineered Microenvironment Enables Durable CO <sub>2</sub> Electroreduction in a Zero‐Gap PEM Electrolyzer

J Jia Chen Wu (Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology 130 Meilong Road Shanghai 200237 China) T Tingting Yu (Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University) J Jianming Gu (School of Materials Science and Engineering Key Laboratory for Ultrafine Materials of Ministry of Education East China University of Science and Technology Shanghai China) H Huai Qin Fu (School of Environment and Science, Gold Coast Campus) Z Ziwei Ye H Hai Yang Yuan (Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China) C Cheng Lian (State Key Laboratory of Chemical Engineering, School of Chemistry and Molecular Engineering) H Huiliang Cao (School of Materials Science and Engineering Key Laboratory for Ultrafine Materials of Ministry of Education East China University of Science and Technology Shanghai China) H Hua Gui Yang (Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China) P Peng Fei Liu (Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China)

Abstract

ABSTRACT CO 2 conversion in proton exchange membrane (PEM) electrolysis systems offers a sustainable pathway for chemical production by eliminating carbonate formation; however, it faces a trade‐off between suppressing the hydrogen evolution reaction and preventing salt precipitation. Here, we resolve this paradox through a molecular‐level engineering strategy by anchoring a mercaptoimidazole ligand on lead‐based catalyst. Operando spectroscopic analyses and theoretical studies reveal that this ligand shell creates a local alkaline microenvironment and establishes a proton‐shielding effect at the catalyst surface. When integrated into a zero‐gap PEM electrolyzer, the catalyst achieves a peak formate Faradaic efficiency of 95.8% and sustains over 90% selectivity at a current density of 600 mA cm −2 . This performance persists under strongly acidic (pH 1.0) and cation‐starved (0.001  M ) conditions. The PEM system delivers extended stability, with over 300 h of continuous operation at industrially relevant current densities. Our work establishes a design strategy that decouples the catalytic microenvironment from the bulk electrolyte and provides a route for durable and selective acidic CO 2 electrolyzers.

Article Details

Volume / Issue Vol. 38, Issue 39
Published July 01, 2026
ISSN 0935-9648
Publisher Unknown Publisher

Journal Info

Advanced Materials

Unknown Publisher

ISSN: 0935-9648 Physical Sciences

Authors (10)

J

Jia Chen Wu

Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology 130 Meilong Road Shanghai 200237 China

T

Tingting Yu

Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University

J

Jianming Gu

School of Materials Science and Engineering Key Laboratory for Ultrafine Materials of Ministry of Education East China University of Science and Technology Shanghai China

H

Huai Qin Fu

School of Environment and Science, Gold Coast Campus

Z

Ziwei Ye

H

Hai Yang Yuan

Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

C

Cheng Lian

State Key Laboratory of Chemical Engineering, School of Chemistry and Molecular Engineering

H

Huiliang Cao

School of Materials Science and Engineering Key Laboratory for Ultrafine Materials of Ministry of Education East China University of Science and Technology Shanghai China

H

Hua Gui Yang

Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China

P

Peng Fei Liu

Key Laboratory for Ultrafine Materials of Ministry of Education, Shanghai Engineering Research Center of Hierarchical Nanomaterials, School of Materials Science and Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China