Fluorination-enabled interface of PtNi electrocatalysts for high-performance high-temperature proton exchange membrane fuel cells

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) bring new opportunities for portable power generation due to their outstanding advantages such as high tolerance to fuel/air impurities and simplified heat/water management. However, carbon-supported nanostructured Pt-based catalysts running at temperatures over 150°C are challenged by the severe aggregation and carbon corrosion, thus leading to poor durability. Herein, we demonstrate that dendritic Pt-Ni nanoparticles supported on fluorinated carbon black (white carbon black) could significantly enhance the performance and durability of HT-PEMFCs as the cathode catalysts running at 160°C due to the strong interaction of the F and Ni atoms to form a Ni_xF_y interface on Pt-Ni nanoparticles. With the formation of a stable Ni_xF_y interface, this integrated HT-PEMFC reached peak power densities of 906 mW cm⁻² and demonstrated excellent durability at 160°C under anhydrous H₂/O₂ conditions. This mitigation strategy was applied to Pt-alloy/C electrocatalysts and resulted in the elimination of Pt dissolution in practical fuel cells. [Figure not available: see fulltext.]