Ni3(BO3)2 as anode material with high capacity and excellent rate performance for sodium-ion batteries

In this paper, Ni-3(BO3)(2) was synthesized via a simple solid-state reaction method and used as anode materials for sodium-ion batteries for the first time. The Ni-3(BO3)(2) exhibits a desodiation capacity of 428.9 mA h g(-1) at 200 mA g(-1) and a high capacity of 304.4 mA h g(-1) even at 2000 mA g(-1). The resulting material also shows a good cycling stability with a capacity retention of 85.4% over 50 cycles. In-situ X-ray diffraction analysis reveals the phase transition behavior of Ni-3(BO3)(2) in the first discharge process. Kinetics analysis reveals that the high-performance sodium storage is dominated by pseudocapacitance, especially at the high rate. These highlights indicate that Ni-3(BO3)(2) would have hopeful prospects as an anode material for sodium-ion batteries.