Abstract
The high theoretical specific capacity of nickel oxide (NiO) makes it attractive as a high-efficiency electrode material for electrochemical energy storage. However, its application is limited due to its inferior electrochemical performance and complicated electrode fabrication process. Here, we developed an in situ fabrication of a graphene-coated, three-dimensional (3D) NiO–Ni structure by simple chemical vapor deposition (CVD). We synthesized NiO layers on Ni foam through a thermal oxidation process; subsequently, we grew graphene layers directly on the surface of NiO after a hydrogen-assisted reduction process. The uniform graphene coating renders high electrical conductivity, structural flexibility and high elastic modulus at atomic thickness. The graphene-coated 3D NiO–Ni structure delivered a high areal density of ∼23 mg cm−2. It also exhibits a high areal capacity of 1.2 mA h cm−2 at 0.1 mA cm−2 for its Li-ion battery performance. The high capacity is attributed to the high surface area of the 3D structure and the unique properties of the graphene layers on the NiO anode. Since the entire process is carried out in one CVD system, the fabrication of such a graphene-coated 3D NiO–Ni anode is simple and scalable for practical applications.
Highlights
The increasing demand for high-efficiency, large-scale electrochemical energy storages has led to an expansion in new developmental efforts for high energy-density lithium-ion batteries (LIBs).[1]
The cross-sectional images display columnar structured nickel oxide (NiO) layers grown on porous Ni foam (Fig. 1(b) and its enlarged FESEM image is included in an inset of Fig. 2(a))
The growth mechanism of NiO on Ni foam is dictated by the thermal diffusion and reaction of Ni2+ and O2À ions in Ni foam according to the Kirkendall effect.[37,38,39]
Summary
Amount of electron transfers, which leads to two- to three-fold superior capacity (600–1100 mA h gÀ1).[5]. The excellent properties and novel design of the graphene coated 3D NiO–Ni anode would expand the development of large-scale LIBs
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.