title: High-Loading Nickel Cobaltate Nanoparticles Anchored on Three-Dimensional N-Doped Graphene as an Efficient Bifunctional Catalyst for Lithium-Oxygen Batteries.
abstract: The lithium-oxygen batteries have been considered as the progressive energy storage equipment for their expected specific energy. To improve the electrochemical catalytic performance in the lithium-oxygen batteries, the NiCo2O4 nanoparticles (NCONPs) are firmly anchored onto the surface of the N-doped reduced graphene oxide (N-rGO) by the hydrothermal method followed by low-temperature calcination. Compared with the pure metallic oxide, the introduction of the rGO can create the high surface area, which give a good performance for ORR (oxygen reduction reaction), and improve the electrical conductivity between the NCONPs. The high-loading NCONPs also ensure the material to have great catalytic activity for OER (oxygen evolution reaction), and the rGO can be protected by the nanoparticles coating against the side reaction with the Li2O2. The as-synthesized NCO@N-rGO composites deliver a specific surface area (about 242.5 m(2) g(-1)), exhibiting three-dimensional (3D) porous structure, which provides a large passageway for the diffusion of the oxygen and benefits the infiltration of electrolyte and the storage of the discharge products. Owing to these special architectures features and intrinsic materials, the NCO@N-rGO cathode delivers a high specific capacity (6716 mAh g(-1)), great rate performance, and excellent cycling stability with cutoff capacity of 1000 mAh g(-1) (112 cycles) in the lithium-oxygen batteries. The improved electrochemical catalytic activity and the special 3D porous structure make the NCO@N-rGO composites be a promising candidate for Li-O2 batteries.
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Hao
authors.initials: H
authors.lastname: Gong
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Hairong
authors.initials: H
authors.lastname: Xue
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Hu
authors.initials: H
authors.lastname: Guo
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Fan
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xia
authors.affiliation: College of Materials Science and Technology, Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, Nanjing University of Aeronautics and Astronautics , Nanjing 210016, P. R. China.
authors.forename: Jianping
authors.initials: J
authors.lastname: He
keywords: 3D N-doped rGO; NiCo2O4 nanoparticles; efficient bifunctional catalyst; lithium−oxygen batteries; long life