Synergistic coordination engineering and Gd–O species incorporation boost PtFe stability for oxygen reduction reaction

The rational design of Pt-based alloy electrocatalysts is vital to improve the durability and performance of proton exchange membrane fuel cells (PEMFCs). However, the instability caused by transition metal leaching and insufficient particle confinement remains a major challenge. Herein, the development of highly dispersed PtFe alloys with rare-earth Gd doping and carbon confinement (PtFeGd x /N–C) by a synergistic strategy of coordination engineering and Gd–O species incorporation is reported. A nitrogen-doped porous carbon support was synthesized via pyrolysis of ZIF-8 precursors containing EDTA-FeNa and Gd(NO 3 ) 3 , yielding uniformly dispersed Gd–Fe oxide domains. Subsequent wet impregnation and in situ alloying with H 2 PtCl 6 generated highly dispersed PtFeGd x nanoparticles. The optimized PtFeGd40/N–C catalyst exhibited a high half-wave potential of 0.94 V and a mass activity of 0.94 A mg Pt −1 , with only 0.5 % activity loss after 100,000 durability cycles. Structural characterizations confirmed strong coordination among Pt, Fe, and Gd, with Gd predominantly present as oxidized species. DFT calculations revealed that Gd and Gd–O doping effectively modulate the Pt d-band center, optimize intermediate adsorption energies, and reduce the reaction barrier to 0.332 eV. This work highlights the synergistic role of rare-earth doping and carbon confinement in enhancing ORR activity and stability, offering a promising strategy for the development of durable Pt-based electrocatalysts for PEMFCs.