Template‐Based Structured Electrodes for High Power and Durable Proton Exchange Membrane Fuel Cells

ABSTRACT

As global interest in commercialization of proton exchange membrane fuel cells (PEMFCs) continues to grow, there is an urgent need to address challenges related to the cost, power, and durability of membrane electrode assemblies (MEAs). In conventional cathode electrodes, the disordered microstructure and tortuous transport pathways result in poor catalyst utilization, sluggish mass transport, and low proton conductivity, ultimately constraining overall performance. Templates with customized patterns to precisely control electrode architectures at the nano‐ and microscale offer a promising strategy to overcome these limitations. Here, we discuss in depth the motivations for developing structured electrodes as alternatives to conventional electrodes and highlight the importance of their structure‐function relationships. Specifically, a comprehensive review is presented on recent advances in the development of template‐based structured electrodes, involving template selection, patterning methods, electrode coating techniques, multiscale engineering, and geometric design. The PEMFC performance of various template‐based structured electrodes is also summarized and tabulated. Finally, current issues and future research directions are proposed to guide the engineering and application of template‐based structured electrodes for next‐generation PEMFCs.