The study reports the synthesis and characterization of PtPb/Pt core/shell nanoplates with large biaxial tensile strains, which exhibit enhanced oxygen reduction reaction (ORR) catalytic activity. The PtPb nanoplates, synthesized using platinum (II) acetylacetonate and lead (II) acetylacetonate as precursors, show high specific and mass activities for ORR, reaching 7.8 mA/cm² and 4.3 A/mgPt at 0.9 V vs. reversible hydrogen electrode (RHE), respectively. Density functional theory (DFT) calculations reveal that the edge-Pt and top (bottom)-Pt (110) facets undergo significant tensile strains, optimizing the Pt-O bond strength. The intermetallic core and uniform 4-layer Pt shell contribute to the high stability of the catalysts, allowing 50,000 voltage cycles with minimal activity decay and no structural or compositional changes. The PtPb nanoplates also demonstrate superior performance in anodic fuel cell reactions, such as methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR).The study reports the synthesis and characterization of PtPb/Pt core/shell nanoplates with large biaxial tensile strains, which exhibit enhanced oxygen reduction reaction (ORR) catalytic activity. The PtPb nanoplates, synthesized using platinum (II) acetylacetonate and lead (II) acetylacetonate as precursors, show high specific and mass activities for ORR, reaching 7.8 mA/cm² and 4.3 A/mgPt at 0.9 V vs. reversible hydrogen electrode (RHE), respectively. Density functional theory (DFT) calculations reveal that the edge-Pt and top (bottom)-Pt (110) facets undergo significant tensile strains, optimizing the Pt-O bond strength. The intermetallic core and uniform 4-layer Pt shell contribute to the high stability of the catalysts, allowing 50,000 voltage cycles with minimal activity decay and no structural or compositional changes. The PtPb nanoplates also demonstrate superior performance in anodic fuel cell reactions, such as methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR).