PtCoNi ternary intermetallic compounds anchored on Co, Ni and N co-doped mesoporous carbon: Synergetic effect between PtCoNi nanoparticles and doped mesoporous carbon promotes the catalytic activity

Highly active and robust electrocatalysts are desired for proton exchange membrane fuel cells. Pt-based intermetallic compounds (IMCs) have been recognized as one of the most promising low-platinum catalysts for fuel cells (FCs). Herein, we report a high-performance IMCs by anchoring ordered PtCoNi ternary nanoparticles on the N, Co and Ni co-doped dodecahedral mesoporous carbon (DMC). While the introduced Co and Ni participate in the formation of PtCoNi IMCs, some of them are doped in the mesoporous carbon and coordinated by N to form Co-N y /Ni-N z dual active centers, which further enhances the electrocatalytic activity towards oxygen reduction reaction. Moreover, the addition of Ni results in a negative shift of the d-band center of Pt as compared to the Pt/DMC and Pt 3 Co/DMC, making it easier to adsorb oxygen on the surface. As expected, our optimal sample Pt 3 Co 0.7 Ni 0.3 /DMC exhibits excellent performance with mass activity and specific activity of 1.32 A mg −1 Pt and 1.98 mA cm −2 at 0.9 V, which are 7.33 and 6.19 times that of commercial Pt/C, respectively. The Pt 3 Co 0.7 Ni 0.3 /DMC also reveals much better cathodic performance in an H 2 -air single fuel cell than commercial Pt/C catalyst with a power density of 0.802 W cm −2 . This work provides critical sights into constructing efficient catalysts by ternary intermetallic strategy and synergetic effect between active components and support.