Durable Fuel Cell Cathode Enabled by Pt Embedded Nanoscale Carbon Network via a Scalable Process

ABSTRACT Proton exchange membrane fuel cells (PEMFC) suffer significant voltage degradation at lower Pt loadings on the cathode. Expedited commercialization and sustainable utilization of scarce resources demand highly durable Pt‐based electrocatalysts produced via rapid, scalable processes. We present Pt nanoparticles (≈ 2 nm) embedded in a nanoscale carbon network, produced via controlled‐atmosphere flame spray pyrolysis, where native Pt nuclei serve as structural guides for the nanoscale overlayer. The gas‐phase‐derived porous catalyst exhibits high accessibility to Pt and uncompromised oxygen reduction activity upon activation and demonstrates at least fourfold lower performance loss at high current densities and fivefold lower electrochemical active surface area loss compared to state‐of‐the‐art alternatives in low‐Pt‐content fuel cells. The strong interfacial coordination between Pt and its surface‐grown carbon network, combined with the continuous, favorable structural evolution of the catalyst and catalyst layer, remarkably suppresses Pt degradation mechanisms, including ionomer poisoning and Pt dissolution, facilitates H + and O 2 transport to the catalyst, and ensures sustained performance under harsh fuel cell operating conditions.