title: MnO2Nanofilms on Nitrogen-Doped Hollow Graphene Spheres as a High-Performance Electrocatalyst for Oxygen Reduction Reaction.
abstract: Platinum is commonly chosen as an electrocatalyst used for oxygen reduction reaction (ORR). In this study, we report an active catalyst composed of MnO2nanofilms grown directly on nitrogen-doped hollow graphene spheres, which exhibits high activity toward ORR with positive onset potential (0.94 V vs RHE), large current density (5.2 mA cm-2), and perfect stability. Significantly, when it was used as catalyst for air electrode, a zinc-air battery exhibited a high power density (82 mW cm-2) and specific capacities (744 mA h g-1) comparable to that with Pt/C (20 wt %) as air cathode. The enhanced activity is ascribed to the synergistic interaction between MnO2and the doped hollow carbon nanomaterials. This easy and cheap method paves a way of synthesizing high-performance electrocatalysts for ORR.
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qiangmin
authors.initials: Q
authors.lastname: Yu
authors.forename: Jiaoxing
authors.initials: J
authors.lastname: Xu
authors.forename: Chuxin
authors.initials: C
authors.lastname: Wu
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Jianshuo
authors.initials: J
authors.lastname: Zhang
authors.forename: Lunhui
authors.identifier: http://orcid.org/0000-0003-1615-4058
authors.initials: L
authors.lastname: Guan
keywords: Zn−air battery; nitrogen-doped graphene; oxygen reduction reaction; synergistic effect