Well-dispersed Pt/Nb 2 O 5 on zeolitic imidazolate framework derived nitrogen-doped carbon for efficient oxygen reduction reaction.

In this work, an advanced hybrid material construction by cooperating niobium pentoxide (Nb2O5) nanoparticles with nitrogen-doped carbon (NC) derived from ZIF-8 dodecahedrons was prepared and used as a support, referred to as Nb2O5/NC. Pt nanoparticles (NPs) was dispersed onto Nb2O5/NC by a simple impregnation reduction method. The obtained Pt/Nb2O5/NC electrocatalyst showed high ORR activity due to three-phase mutual contacting structure with well-dispersed Pt and Nb2O5 NPs. In addition, the conductive NC is benefit to electron transfer while the induced Nb2O5 can regulate electronic structure of Pt element and anchor Pt NPs, thereby enhancing the ORR activity and stability. The half-wave potential (E1/2) for Pt/Nb2O5/NC is 0.886V, which is higher than that of Pt/NC (E1/2=0.826V). The stability examinations demonstrated that Pt/Nb2O5/NC showed higher electrocatalytic durability than Pt/NC. Our work provides a new direction for synthesis and structural design of precious metal/oxides hybrid structured electrocatalysts.