High-quality and deeply excavated PtPdNi nanocubes as efficient catalysts toward oxygen reduction reaction

Abstract

The oxygen reduction reaction (ORR) on the cathode of a polymer electrolyte fuel cell requires the use of a catalyst based on Pt, one of the most expensive metals on the earth. A number of strategies, including optimization of a different metal into the core, have been investigated to enhance the activity of a Pt-based catalyst and thus reduce the loading of Pt. By dedicating to compounding high catalytic activity Pt2.7Pd0.3Ni concave cubic with high index crystal face, the paper shows that concave structures can offer more active site and high level of catalytic activity and if mixed with other metal, decrease the proportion of Pt and improve its mass activity. The paper also makes an exploration into the theory and conditions behind the formation of Pt2.7Pd0.3Ni concave cubic structure, and investigates the difference it demonstrates by modifying the reactive conditions. The results of the oxygen reduction performance of the electrochemical test are as follows: the concave cube-shaped Pt-Pd-Ni catalyst has a mass activity of 1.28 A mgPt–1 at 0.9 V, its highest mass activity is 8.20 times that of commercial Pt/C, and its specific activity is 8.68 times of that commercial Pt/C. And the Pt-Pd-Ni ternary nanocage has excellent structural invariance. After the stability test, there is no obvious structural change and performance degradation in the nanostructure.