Optimizing oxygen reduction reaction performance in Pt-based catalysts through Fe/Ce dual-component interface engineering on nitrogen-doped carbon†

Abstract

The advancement of high-efficiency Pt catalysts with reduced Pt loading is crucial for proton exchange membrane fuel cells (PEMFCs). This research presents a methodology that significantly increases the performance of Pt/C through the interactions between Pt and Fe–N_x/Ce–N_x on carbon, thereby effectively reducing Pt consumption. Density functional theory (DFT) calculations indicate that the presence of Fe–N_x/Ce–N_x together enhances the strong interaction between Pt and FeCe–NC, decreasing the d-band energy level (εd) of Pt, which leads to the reduction of O* adsorption and acceleration of desorption at the Pt sites. Consequently, the Pt/FeCe–NC demonstrates exceptional performance for the ORR. The Pt/FeCe–NC has an E_1/2 of 0.927 V and decays by only 7 mV after 30 000 accelerated stress test (AST) cycles under acidic conditions. Furthermore, the Pt/FeCe–NC (2.14 W cm⁻²) surpasses Pt/C (1.78 W cm⁻²) regarding peak power density in PEMFCs. This innovative approach clarifies the interactions between Pt and Fe–N_x/Ce–N_x, providing a framework for the design of advanced catalysts.