Surfactant-driven shape evolution to sub-3 nm Pt-rich Pt3Ni dodecahedrons as efficient electrocatalyst for oxygen reduction reaction

Abstract

BackgroundDeveloping an economical and durable high-activity Pt-based electrocatalyst to alleviate the slow kinetics of the oxygen reduction reaction (ORR) is crucial for fuel cells. The shape-controllable Pt3Ni alloy catalyst with high electrocatalytic properties is regarded as one of the most efficacious electrocatalysts capable of accelerating ORR kinetics. MethodsHere, sub-3 nm Pt-rich Pt3Ni dodecahedrons (DCs) has been developed via surfactant-driven shape evolution route as effective electrocatalysts for ORR. Significant findingsThe Pt3Ni DCs exhibit 4.3-fold improvement for mass activity and 4.7-fold improvement for specific activity respect to pristine Pt/C catalyst. Moreover, the remaining specific activity on Pt3Ni DCs is 6.7 times larger relative to pristine Pt/C catalyst after 20,000 scanning cycles. Such electrocatalytic performance enhancement is attributed to the ensemble effect including the dodecahedrons shape and synergistic effect between Pt and Ni atoms. We believe that our synthetic approach would provide new avenues toward the formation of polyhedron structures.