NiO/Ni nanocomposites embedded in 3D porous carbon with high performance for lithium-ion storage

The high energy storage devices such as lithium-ion batteries (LIBs) have recently attracted extensive attention, and massive efforts have been made to synthesize the high-performance electrodes for Li-ion storage. Here, a facile in situ synthesis method was proposed to prepare the NiO/Ni nanocomposites embedded in three-dimensional (3D) porous carbon network (denoted as NiO/Ni⊕C). The phase component and microstructure of the NiO/Ni⊕C were detected by using X-ray diffraction, scanning electron microscope and transmission electron microscopy. The NiO/Ni nanocomposites with the particle size of approximately 20–50 nm were uniformly dispersed in the 3D porous carbon matrix. The 3D carbon network is in favor of electrical conductivity, and effectively alleviates the volume effect during lithiation–delithiation processes, and thus help the electrode achieve high electrochemistry performance. The NiO/Ni⊕C electrodes possess a reversible specific capacity of 934 mAh g−1 at a current density of 300 mA g−1, and exhibit a superior rate performance with a specific capacity of 505 mAh g−1 at a current density of 2 A g−1. The NiO/Ni⊕C electrodes maintained a specific capacity of up to 683 mAh g−1 even after 1000 cycles at a current density of 1 A g−1.