Novel three-dimensional flower-like porous Al2O3 nanosheets anchoring hollow NiO nanoparticles for high-efficiency lithium ion batteries

Abstract

In this report, unique 3D flower-like porous Al₂O₃ nanosheets anchoring hollow NiO nanoparticles (FH-NiO@Al₂O₃) are designed and prepared via a controllable hydrothermal method. In this strategy, we directly synthesize flower-like Ni₂Al(CO₃)₂(OH)₃ nanoplates instead of coating Al₂O₃ nanosheets later. This advanced flower-like embedded structure can efficiently afford a large specific surface area for plenty of active sites and a continuous contact area between the active materials and electrolyte. Furthermore, Al₂O₃ coating can prevent active materials from pulverization, agglomeration and dropping off during electrochemical reactions. Importantly, the porous structure and hollow nanoparticles can mitigate possible volume changes. It is no wonder that the FH-NiO@Al₂O₃ demonstrates superior Li-storage performances (1217 mA h g⁻¹ at 500 mA g⁻¹, 97% retention after 300 cycles).