Downshifting Pt d-band center by ordered Pt1Co1 NCs interfacial synergy: Enhanced anti-poisoning and bifunctional electrocatalysis

Designed ordered Pt 1 Co 1 nanocrystals anchored on N-doped carbon with optimized Pt/Co ratio for bifunctional ORR and MOR. • Achieved superior ORR performance: mass activity of 0.734 mA/μg Pt and specific activity of 1.725 mA/cm 2 , outperforming Pt/C by 4.2 and 6.2 times, respectively. • Revealed the synergy of ordered structure and metal-support interaction (SMSI) for electronic modulation (downshifted Pt d-band) and geometric stabilization. • Provided a universal design principle for high-performance Pt-based bifunctional electrocatalysts via structural ordering and support engineering. The practical deployment of fuel cells (FCs) faces significant obstacles stemming from the surface poisoning of electrocatalysts by carbonaceous intermediates (primarily CO) and the intrinsically sluggish reaction kinetics of the oxygen reduction reaction (ORR) at the cathode. Herein, we report the synthesis of ordered PtCo nanocrystals anchored on a nitrogen-doped carbon (NC) support with precisely controlled atomic ratios. The incorporation of Co atoms into the Pt lattice induces a downshift of the Pt d -band center, substantially weakening the adsorption strength of CO and other oxygen intermediates on the catalyst surface. In the CO stripping experiment, the CO oxidation peak potential of Pt 1 Co 1 NCs was observed at 0.587 V, which is 137 mV lower than that of 20% commercial Pt/C (0.724 V). This significant negative shift directly confirms the enhanced CO tolerance of the Pt₁Co₁ NCs catalyst. Furthermore, the Pt 1 Co 1 NCs catalyst demonstrated significantly enhanced bifunctional activity. Specifically, it delivered mass activities (MA) of 0.734 mA/μg Pt for the ORR and 0.932 mA/μg Pt for the MOR, outperforming commercial Pt/C by factors of 4.2 and 3.7, respectively. Download: Download high-res image (324KB) Download: Download full-size image