Alleviating Temperature-Induced Oxidative Poisoning in Oxophilic Pd for Methanol Electrocatalysis

While simultaneously highly active and durable catalysts for the methanol-oxidation reaction (MOR) are rare, their performance at device-relevant elevated temperatures has been barely explored. In this work, we design oxophilic Ni-doped Pd nanowire morphology, which can impart multiple catalyst-electrode contacts, achieving a superior MOR mass activity of ∼3.5 A mg–1 and commendable stability with <0.8% degradation/hour. Through comprehensive studies across varying temperatures and potentials, we reveal significant performance deviations at high temperatures (HT) compared to conventional room-temperature data, as well as stark behavioral contrasts between Pt and Pd. The Pd nanowires exhibit superior resistance to surface oxidation at HT, thereby retaining their high MOR performance with 2-fold deviations in activation energy values with varied applied potentials, while Pt barely shows any variation. To corroborate this, we systematically map the temperature-dependent −OH formation vs utilization kinetics and establish a direct correlation with −OH tolerance. Due to superior activation by resisting −OH poisoning, the Pd nanowires widen their theoretical operating potential window by over 180% more than in Pt. While Pd is already recognized for its superior CO tolerance, our study establishes that it is also more resilient to OH poisoning at elevated temperatures, enabling simultaneous high activity and activation.