Abstract:
Nickel oxide (NiO) is known for its remarkable theoretical specific capacity, making it a highly appealing
option for electrode materials in electrochemical energy storage applications. Nevertheless, its practical
use is limited by poor electrochemical performance and complicated electrode fabrication processes. To
address these issues, we propose a new anode design comprising an intermediate NiO nanoarray layer
and a carbon coating layer grown directly on a three-dimensional (3D) conductive nickel foam substrate,
designated as C@NiO@Ni foam. This anode with a high NiO mass loading of 5–6 mg cm−2 is fabricated
by a two-step process: thermal oxidation of the nickel foam, followed by carbon coating. The 3D
architecture, with its large surface area, significantly enhances the contact between the electrode and
electrolyte, thereby shortening the Li-ion diffusion pathway. Additionally, the carbon layer plays a crucial
role in accommodating the volume changes of NiO during cycling, preventing the detachment of NiO
from the Ni foam substrate, and enhancing the electronic conductivity of the C@NiO@Ni foam. The
resulting porous C@NiO@Ni anode was thoroughly analyzed using scanning electron microscopy (SEM),
X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). When used as an anode
material for lithium-ion batteries (LIBs), this anode showcased an impressive reversible capacity of
around 678 mA h g−1 at 0.1C after 100 cycles. Furthermore, it demonstrated excellent electrochemical
performance at a high current, sustaining a specific capacity of 387 mA h g−1 at 1C after 100 cycles.
