Operando Magnetic Resonance Imaging for Visualizing Electrochemical Triple‐Phase Boundary

W Wen‐Long Jiang (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) S Shuo‐Hui Cao (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) C Chun‐Yu Qiu (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) H Hui‐Jun Sun (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) L Li‐Na Wang (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) J Jun‐Bo Sheng (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) L Li‐Fei Ji (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) S Shuo Liu Z Zu‐Rong Ni (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) S Shu‐Hu Yin (School of Microelectronics and School of Integrated Circuits Nantong University Nantong 226019 P.R. China) X Xiao‐Ping Zhang (State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China) Y Yan‐Xia Jiang (State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China) Y Yu‐Cheng Wang (State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen China) Z Zhi‐You Zhou (State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen China) Z Zhong Chen S Shi‐Gang Sun (State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China)

Abstract

Abstract The triple‐phase boundary (TPB) is a complex interface where gas, liquid, and solid phases converge, crucially regulating the efficiency and performance of many electrochemical devices including fuel cells and batteries. However, conventional characterization techniques struggle to capture the dynamic processes and flooding at TPB. To address this, we develop operando electrochemical magnetic resonance imaging (EC‐MRI), an inherently non‐invasive technique sensitive to 1 H, which probes both bulk and boundary regions, enabling real‐time visualization of TPB evolution and a deeper understanding of its function at the device level under operational conditions. In a study of proton exchange membrane fuel cell (PEMFC), with a focus on the kinetically sluggish O 2 reduction reaction in the cathode, operando EC‐MRI quantitatively illustrates the interplay between power output, water content, and TPB evolution. It reveals that the TPB maps undergo significant spatial and dynamic variations, with TPB deterioration, rather than apparent water accumulation, directly triggering flooding, as proved using catalysts with different water generation and adsorption capabilities. Our finding opens new perspectives on water management and TPB design, with potential applications in other critical electrochemical processes such as H 2 oxidation, CO 2 reduction, and N 2 reduction, underscoring the value of operando EC‐MRI for real‐time diagnostics of electrochemical devices.

Article Details

Volume / Issue Vol. 64, Issue 31
Published July 28, 2025
ISSN 1433-7851
Publisher Wiley

Journal Info

Angewandte Chemie International Edition

Wiley

ISSN: 1433-7851 Physical Sciences

Authors (16)

W

Wen‐Long Jiang

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

S

Shuo‐Hui Cao

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

C

Chun‐Yu Qiu

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

H

Hui‐Jun Sun

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

L

Li‐Na Wang

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

J

Jun‐Bo Sheng

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

L

Li‐Fei Ji

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

S

Shuo Liu

Z

Zu‐Rong Ni

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

S

Shu‐Hu Yin

School of Microelectronics and School of Integrated Circuits Nantong University Nantong 226019 P.R. China

X

Xiao‐Ping Zhang

State Key Laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis & Instrumentation Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance School of Electronic Science and Engineering College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P.R. China

Y

Yan‐Xia Jiang

State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China

Y

Yu‐Cheng Wang

State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen China

Z

Zhi‐You Zhou

State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen China

Z

Zhong Chen

S

Shi‐Gang Sun

State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Xiamen P. R. China