S-doped carbon anchoring PtCo intermetallic nanoparticles for efficient proton exchange membrane fuel cells based on molecularly engineered design

Abstract

Enhanced ordered intermetallic compounds excel in catalyzing the oxygen reduction reaction (ORR). We introduce a novel synthesis strategy based on molecularly engineered to address challenges in high-temperature annealing. It involves the synthesis of carbon platforms with rich edge sites, which serve as effective anchoring points for nanoparticles. By utilizing sulfur anchoring, we synthesize ordered Pt–Co intermetallic with Pt-rich shells (o-PtCo@Pt) that exhibit remarkable ORR performance. Ordered arrangement of Pt–Co endows Pt-shell with compression stress and enhances the oxidation resistance of Pt/Co sites. O–PtCo@Pt exhibits high mass activity (MA, 0.53 A mgPt−1) and specific activity (SA, 1.17 mA cm−2). It exhibits remarkable as cathodic catalyst in proton exchange membrane fuel cells. It achieves power density of 1.14 W cm−2 at 2.0 A cm−2, with MA of 0.50 A mgPt−1 at 0.9 V. It maintains stability with only 8 % power density loss after 30,000 cycles, retaining MA of 0.35 A mgPt−1.