Year: 2026
Type: preprint
Abstract: Optimal catalyst-layer fabrication strategies for proton exchange membrane fuel cells (PEMFC) are often developed under a single set of operating conditions, making it unclear whether the resulting design rules remain valid across different operating environments. Here, we show that operating conditions not only shift catalyst-layer optima but re-order the fabrication parameters governing performance. By combining application-relevant gas diffusion electrode (GDE) measurements with machine-learning analysis, we map the multidimensional fabrication–performance space of Pt/C oxygen reduction reaction (ORR) catalyst layers across humid low-temperature (30 °C, relative humidity (RH) > 80%) and dry high-temperature (120 °C, RH < 10%) regimes. The optimal catalyst-layer fabrication parameters change significantly between conditions, and their relative importance re-orders. While ionomer- and Pt-concentration-related parameters dominate performance under humid low temperature conditions, process- and deposition-related parameters become governing factors under dry high-temperature operation. These results demonstrate that catalyst-layer optimization is inherently condition-dependent and challenge the notion of universal fabrication rules. More broadly, this work establishes operating-condition-dependent design spaces as a fundamental principle of catalyst-layer engineering, providing a framework for developing electrodes optimized for the specific operating conditions of next-generation PEMFCs.
Source: ChemRxiv
Institutions: University of Bern, University of Nevada, Reno
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7208769930