Electrocatalytic Performance and Durability of Pt Catalysts for ORR via a One-Pot Cyanamide Modification Strategy

Commercial Pt/C catalysts are widely used for the oxygen reduction reaction (ORR) at the cathode of proton exchange membrane fuel cells, but their activity and durability remain limited by the interfacial environment and the adsorption behavior of oxygenated intermediates. Herein, we report a cyanamide-assisted wet-chemical strategy to prepare a cyanamide-modified Pt/C catalyst, denoted as Cy-Pt@C. In this system, cyanamide is introduced during Pt nucleation and growth, enabling modulation of the Pt interfacial chemical environment and improving nanoparticle dispersion on the carbon support. Electrochemical measurements in 0.1 M HClO 4 show that Cy-Pt@C exhibits a half-wave potential of 0.851 V, which is more positive than those of Pt@Cy/C (0.830 V), Pt@Cy (0.824 V), Pt@C (0.834 V), and commercial Pt/C (0.815 V). At 0.9 V vs RHE, Cy-Pt@C delivers a mass activity of 0.10 A mg Pt –1 and a specific activity of 0.13 mA cm –2, both higher than those of the Pt@C control catalyst. In addition, Cy-Pt@C shows low H 2 O 2 yield, an electron transfer number (n) close to 4, and favorable durability during accelerated cycling. After 30,000 potential cycles, the half-wave potential remains at 0.846 V, indicating limited activity loss. These results suggest that cyanamide-assisted interfacial regulation is an effective approach for tuning the Pt/carbon interfacial environment and improving acidic ORR performance in half-cell measurements.