Ordered Bimetallic Pt‐Based Intermetallic Catalysts Enable Highly Efficient Oxygen Reduction Reaction in Zinc–Air Batteries

Abstract

ABSTRACT The advancement of low‐cost Pt‐based intermetallic catalysts is of substantial importance for the effective implementation of high‐efficiency zinc–air batteries (ZABs). However, designing efficient catalysts that exhibit both high catalytic activity and stability presents significant challenges. To overcome this issue, we have designed a hybrid catalyst comprising ordered PtM (M = Fe, Co, and Ni) intermetallic nanoparticles uniformly anchored to atomically dispersed M‐N‐C substrates by integrating a freezing microchemical displacement method with a high‐temperature anchoring‐reduction strategy. The Pt‐NC layer formed during synthesis inhibits Pt nanoparticle migration and aggregation during annealing, which represents a key advantage over traditional methods that often require thick protective coatings. X‐ray absorption fine structure analysis reveals that Pt–N bonds form between the nanoparticles and M‐N‐C support, building strong metal‐support interactions through electron transfer and thus significantly enhancing structural stability. Furthermore, theoretical calculations reveal that the structurally ordered PtM intermetallics induce strong electron effects and optimize the d‐band center of Pt. The synergistic effects of the ordered PtM electronic structure and its interaction with the M‐N‐C substrates result in significantly enhanced ORR activity for PtCo@CoNC. This catalyst achieves a mass activity of 1.23 mA/µg Pt and a specific activity of 1.14 mA/cm 2 Pt , outperforming the commercial Pt/C catalyst, which shows values of 0.16 mA/µg Pt and 0.22 mA/cm 2 Pt . When utilized in ZABs, the PtCo@CoNC demonstrates superior performance, yielding a higher open‐circuit voltage (1.486 V) and peak power density (179.47 mW cm −2 ) compared to Pt/C‐based devices, highlighting the practical advantages of the ordered PtM@MNC design.