A novel probe cell approach for rapid, localized, room temperature electrochemical analysis of catalyst layers in proton exchange membrane fuel cells

The development of proton exchange membrane fuel cell (PEMFC) materials is constrained by time-intensive fabrication and testing workflows, limiting the speed of materials discovery and optimization. Moreover, existing rapid screening techniques often fail to replicate fuel cell conditions, restricting their relevance for device-level performance evaluation. In this preliminary work, we designed and explored a novel probe cell platform for rapid and localized electrochemical characterization of membrane electrode assemblies (MEAs). The probe electrode enables measurements on a small active area of 0.31 cm² over a standard 25 cm² MEA, allowing multiple spatially resolved analyses on a single membrane-electrode-assembly. Using catalyst coated substrate (CCS) configurations, an optimized protocol yielded consistent polarization and cyclic voltammetry data across multiple MEA locations for both Nafion™-based and Pemion®-based systems. Electrochemical surface area (ECSA) measurements further confirmed reliable assessment of catalyst utilization. Compared to conventional fuel cell testing, the probe cell provides comparable electrochemical trends at ambient temperature while significantly reducing data acquisition time. This approach offers a practical pathway toward accelerated screening of catalyst layers and ionomer systems, supporting the development of next-generation PEMFC materials.