Porous NaTi2(PO4)3@C nanocubes as improved anode for sodium-ion batteries

The NASICON-type NaTi2(PO4)3 has drawn much attention as anode material for sodium-ion batteries owing to its stable structural characteristics and low cost. Nevertheless, the insulating property of NaTi2(PO4)3 and the high working potential of about 2.1 V vs. Na+/Na lead to its poor cycling stability, low rate performance as well as inferior capacity. In this work, we synthesize the porous NaTi2(PO4)3@C nanocubes by hydrothermal method and a subsequent coating process with using oleic acid as the carbon source. When utilized as the anode for sodium-ion battery in the voltage range between 0.01 V and 3.0 V, The as-synthesized porous NaTi2(PO4)3@C nanocubes deliver a discharge capacity of 201 mAh·g−1 at the current density of 100 mA g−1 after 100 cycles. Additionally, the reserved capacity of 140 mAh·g−1 could be achieved at the current density of 1 A g−1 after 1000 cycles.