Directed construction of high-stability PtPd alloys for methanol electrooxidation

Directed construction of composition-controlled PtPd alloy catalysts. • Pt 3 Pd 3 /NC achieves 1.94 nm particle size and highest metallic state ratio. • Graphitic-N induced strong metal-support interaction enhances stability. • Mass activity reaches 4892 mA mg −1 metal , outperforming most noble-metal catalysts. • In situ SERS confirms non-CO (formate) pathway, avoiding CO poisoning. Direct methanol fuel cells (DMFCs) suffer from the high Nost, CO poisoning, and insufficient durability of Pt-based anodes. Alloying Pt with Pd offers a promising route to enhance CO tolerance, yet the stability of PtPd nanoparticles under operating conditions remains a critical challenge. Here, we report composition-controlled Pt x Pd y (x + y = 6) alloy catalysts supported on ZIF-8-derived nitrogen-doped carbon (NC). The equimolar Pt 3 Pd 3 /NC exhibits the smallest particle size (1.94 nm), highest metallic Pt 0 (73.1%) and Pd 0 (79.8%), and strong electron donation from graphitic-N in NC. This catalyst delivers an exceptional mass activity of 4892.0 mA mg −1 metal for methanol oxidation in alkaline media, with 93.3% retention after 500 cycles and a retained current density of 2156.4 mA mg −1 metal after 10,800 s. In situ surface-enhanced Raman spectroscopy reveals a non-CO (formate) pathway, completely avoiding CO poisoning. This work establishes a composition-structure-activity-stability relationship for PtPd alloys and provides a rational design strategy for high-performance, durable DMFC anodes.