Ternary PtCoTe Intermetallic Compound as a High-Activity and High-Stability Oxygen Reduction Reaction Catalyst

Pt-based alloy catalysts can substantially reduce the amount of Pt required in proton exchange membrane fuel cells. However, they encounter some critical challenges, including the dissolution of base metals and the coalescence of nanoparticles during the oxygen reduction reaction (ORR). In this study, we present a facile synthesis of an ordered O-PtCoTe/C intermetallic compound catalyst through simple impregnation combined with thermal annealing. The optimized catalyst exhibits exceptional ORR performance with mass activity (1.04 A mg_Pt^–1) and specific activity (1.19 mA cm^–2) reaching approximately 6.1-fold and 4.9-fold enhancements over commercial Pt/C (0.17 A mg_Pt^–1, 0.24 mA cm^–2), respectively. Remarkably, the O-PtCoTe/C catalyst also demonstrates outstanding stability, with only 12% loss in mass activity after 60,000 potential cycles, whereas the commercial Pt/C catalyst suffers 53% activity loss after only 30,000 potential cycles. Poststability characterization of the samples reveals that the introduction of Te effectively suppresses Co leaching and nanoparticle coalescence through electronic interactions. This study provides a novel pathway for designing durable Pt-based intermetallic electrocatalysts with simultaneously improved activity and stability for practical fuel cell applications.