Hollow carbon nanorods supported platinum-nickel alloy as high efficient catalysts for oxygen reduction reaction

Platinum group catalysts are still the most effective catalysts for oxygen reduction reaction (ORR) of proton exchange membrane fuel cells. Thus, the high cost and susceptibility to deactivation during working process are becoming more and more prominent with the proceeding of the application. To meet the requirements of enhancing reaction kinetics and decreasing the cost of Pt-based catalysts, we design a N-doped hollow carbon nanorods (HCNR) supported platinum-nickel based catalyst for ORR. Compared with the benchmark commercial Pt/C catalyst, the HCNR supported PtNi catalysts (PtNi/HCNR) show excellent catalytic activity for ORR and long-time running durability. The onset potential (E0) and half wave potential (E1/2) of medium platinum content catalyst (PtNi/HCNR-2) catalyzed ORR are 1.02 V and 0.914 V, separately, which surpass than that of the 20 wt% Pt/C catalyst. Furthermore, PtNi/HCNR-2 catalyzed ORR has a lower Tafel slope (92.05 mV dec−1), faster electron transfer rate, lower H2O2 yield rate and better stability. The synergistic effect between N-doped HCNR and PtNi alloy assures the high performance for ORR. HCNR improves the electrical conductivity, while the doped nitrogen provides "coordination nests" for PtNi catalyst, which provide more catalytic active sites for ORR. PtNi/HNCR-based catalysts have great potential to be low-cost, high performance catalysts for ORR.