From Membranes to Electrodes: Aligned Membrane Electrode Assemblies for Ion-Exchange Membrane Fuel Cells and Water Electrolyzers

Lianqin Wang; Yang Xiao; Shan Guan; Xinyi Cao; Junfeng Zhang; Yan Yin; Tianyou Wang; Michael D. Guiver

doi:10.1007/s41918-025-00269-6

Electrochemical Energy Reviews ›› 2026, Vol. 9 ›› Issue (1) :4 DOI: 10.1007/s41918-025-00269-6

Review Article

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From Membranes to Electrodes: Aligned Membrane Electrode Assemblies for Ion-Exchange Membrane Fuel Cells and Water Electrolyzers

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¹State Key Laboratory of Engines, School of Mechanical Engineering, Tianjin University, 300072, Tianjin, China

²National Industry–Education Platform for Energy Storage, Tianjin University, 300350, Tianjin, China

^a geosign@tju.edu.cn

^b yanyin@tju.edu.cn

^c wangtianyou@tju.edu.cn

^d michael.guiver@outlook.com

Lianqin Wang

Lianqin Wang is currently an Associate Professor at Tianjin University. She received her Master’s degree from Sun Yat-sen University, China, where she specialized in electrocatalysis. She then obtained her Ph.D. degree from the University of Trieste, Italy, conducting research on nanocatalysts. Subsequently, she carried out postdoctoral research at the University of Surrey, UK, focusing on radiation-grafted anion exchange membranes. Her primary research interests include ion exchange membranes, catalysts, fuel cells, and water electrolyzers.

Yang Xiao

Yang Xiao is currently studying for a Ph.D. degree under the guidance of Prof. Tianyou Wang at Tianjin University. She received her M.S. degree in Energy and Power Engineering from Tianjin University in 2024. Her research focuses on the design and application of anion exchange ionomers in water electrolysis.

Shan Guan

Shan Guan is currently studying for a Ph.D. degree under the guidance of Prof. Junfeng Zhang at Tianjin University. He received his M.S. degree in Materials Science and Engineering from Tianjin University in 2024. His research focuses on the design of radiation-grafted functional membranes and their application in water electrolysis.

Xinyi Cao

Xinyi Cao is a master student supervised by Professor Junfeng Zhang from Tianjin University. She received her B.Eng. degree in Energy and Power Engineering from Tianjin University in 2023. Her research focuses on the anion exchange ionomers in water electrolysis.

Junfeng Zhang

Junfeng Zhang is an Associate Professor of Tianjin University, a member of the Chinese Chemical Society and the Royal Society of Chemistry (UK). His research focuses on key materials and devices for fuel cells and water electrolysis, with particular emphasis on membrane electrode assembly design. He was selected for the 2024 Top 2% Scientists list globally. He has published over 100 papers in international journals including Energy Environ. Sci., Adv. Mater., Angew. Chem., Nat. Commun. and Adv. Sci. His work has garnered over 4 600 citations with an H-index of 36.

Yan Yin

Yan Yin is currently a professor in the State Key Laboratory of Engines (SKLE) at Tianjin University, China. She received her Ph.D. degree in 2003 from Yamaguchi University, Japan. She primarily engages in fundamental research on key materials and transport processes in water electrolysis and fuel cells. Her research includes membrane and catalyst design, as well as performance and lifetime prediction of membrane electrode assemblies. She has published over 100 papers in journals such as Nat. Energy, Nat. Commun., and Energ. Environ. Sci., with her work being cited over 8 000 times in SCI publications. She has been selected as a Highly Cited Chinese Researcher by Elsevier and included in the list of the top 2% of scientists worldwide in terms of both “Annual Impact” and “Lifetime Scientific Impact”.

Tianyou Wang

Tianyou Wang is a professor at Tianjin University. He has been dedicated to theoretical and technological research on efficient and clean combustion in internal combustion engines, including the physical mechanisms of core processes such as droplet collision, fragmentation, and evaporation; multiscale characteristics of in-cylinder flow in internal combustion engines; variable pressure differential airflow testing methods; and comprehensive airflow evaluation methods. He invented the parametric design technology for air passages and developed an internal combustion engine airflow test bench with fully independent intellectual property rights. He has published over 100 academic papers and holds more than 20 authorized invention patents.

Michael D. Guiver

Michael D. Guiver joined Tianjin University as a professor in 2014. He obtained his Ph.D. degree in Chemistry from Carleton University, Canada, in 1988. Previously, he worked at the National Research Council Canada from 1987 to 2014. He was a visiting professor from 2009 to 2013 at Hanyang University, South Korea. He served as Editor for the Journal of Membrane Science for 12 years from 2009 to 2020, and is currently Field Chief Editor for Frontiers in Membrane Science and Technology (since 2022). He is a Fellow of the Royal Society of Chemistry and an ACS Poly Fellow. His research interests are in polymeric membranes for ion-exchange and gas separation applications. He has published over 300 articles and 11 book chapters and holds~25 patents and patent applications in the area of polymeric membrane materials.

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Abstract

Ion-exchange membrane fuel cells (IEMFCs) and ion-exchange membrane water electrolyzers (IEMWEs) have become the focus of research in the field of clean energy conversion. However, the problem of membrane and electrode species transport is still a bottleneck for their industrialization. Biological behavior in nature provides valuable insights into the design of energy conversion devices. The phenomenon in which fish groups achieve efficient passage through orderly arrangement reveals the unique advantage of aligned transport structures in increasing the transport efficiency of species. This evolutionary law from disorder to order is reflected in energy devices as the oriented design of membrane electrode assemblies (MEAs). Conventional MEAs suffer from inefficient mass transport, catalyst agglomeration, and insufficient ion conductivity, which are rooted in transport disorder caused by isotropic channels. Novel uniaxial transport structures construct a directly connected path for ion conduction, gas diffusion, and water transport through-plane to the overall alignment of the MEAs, and this design significantly reduces the internal resistance and increases the energy density and conversion efficiency. Starting with ion-exchange membranes, this review describes the importance of overall alignment from membranes to electrodes for ion, gas, and water transport and systematically compares the differences in transport mechanisms among isotropic, anisotropic, and through-plane aligned structures. The synthesis methods and fabrication techniques for achieving these aligned transport architectures are summarized, and their structural stability and device stability are evaluated. The prospects for the industrialization of uniaxially oriented MEAs are envisioned, and possible solutions to existing challenges are proposed.

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Keywords

Aligned structure / Uniaxial transport / Membrane electrode assembly / Ion-exchange membrane / Fuel cell / Water electrolyzer

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Lianqin Wang, Yang Xiao, Shan Guan, Xinyi Cao, Junfeng Zhang, Yan Yin, Tianyou Wang, Michael D. Guiver. From Membranes to Electrodes: Aligned Membrane Electrode Assemblies for Ion-Exchange Membrane Fuel Cells and Water Electrolyzers. Electrochemical Energy Reviews, 2026, 9(1): 4 DOI:10.1007/s41918-025-00269-6

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