Biomimetic structures for water management in proton exchange membrane fuel cells: A review

Water management in proton exchange membrane fuel cells (PEMFCs) is a critical factor affecting performance metrics such as power density, and plays a vital role in the service life and durability of the proton exchange membrane. By emulating biological designs, biomimetic technique has driven the development of novel materials and structures for fuel cells, propelling their innovation and sustainable development. This study systematically reviews the progress from biomimetic innovations to their engineering applications within the field of water management for PEMFCs. Then, this review sequentially explores: biomimetic flow field designs based on leaf vein/root system fractal theory; biomimetic gas diffusion layer (GDL) structures; and biomimetic catalyst layer and membrane designs enabling molecular-scale water management. By comparing the advantages and limitations of different biomimetic strategies in transport efficiency, drainage capacity, and stability, this study reveals the potential value of biomimetic approaches in improving water management performance in fuel cells. In view of the remaining challenges associated with manufacturing complexity, durability assessment, and scalable fabrication of biomimetic structures, this work further points out that future research may build on the synergy among materials science, biology, and advanced manufacturing technologies, while introducing data-driven methods as auxiliary tools to support the optimized design and performance evaluation of biomimetic structures.