Rational Design of Multifunctional Nano–Architected Coatings for Bipolar Plates in Proton Exchange Membrane Fuel Cells

ABSTRACT Proton exchange membrane fuel cells (PEMFCs) require advanced bipolar plate coatings to enhance efficiency, durability, and commercialization potential. This review presents a systematic framework for evaluating and designing bipolar plate coatings, integrating material selection, performance metrics, deposition techniques, and future innovation strategies. Four primary coating categories, namely carbon, metallic, compound, and conductive polymers, are assessed within this framework, considering electrical conductivity, interfacial contact resistance, corrosion resistance, mechanical stability, and hydrophobicity. The review also examines deposition scalability and trade–offs, highlighting the potential of artificial intelligence–driven material design and carbon–ceramic–polymer hybrid architectures to overcome current limitations. By synthesizing existing knowledge into an overarching design and evaluation framework, this work guides the development of multifunctional coatings that balance conductivity, durability, and cost‐effectiveness, accelerating PEMFCs' advancement and sustainable energy adoption.