Graphene-Supported NaTi₂(PO₄)₃as a High Rate Anode Material for Aqueous Sodium Ion Batteries

NaTi 2 (PO 4 ) 3 /graphene composites had been synthesized by a sol-gel and post heat-treatment approach. Different graphene content in the final NaTi 2 (PO 4 ) 3 /graphene composites had a large influence on the electrochemical performance of aqueous rechargeable sodium ion batteries (NIBs), especially the rate property. Among the prepared NaTi 2 (PO 4 ) 3 /graphene composites, the 6.84% graphene contained NaTi 2 (PO 4 ) 3 sample displayed the highest capacity, which was about 63.5 mA h g −1 at 20 C, and retained 71% of the initial capacity after 2000 cycles. Furthermore, this sample also exhibited good cycling performance in non-aqueous NIBs, with a reversible capacity of 102 mA h g −1 after 700 cycles at 100 mA g −1 . The graphene plays a critical role in enhancing the cycling stability and rate property of NaTi 2 (PO 4 ) 3 in rechargeable NIBs. Composited with appropriate amount of grephene, NaTi 2 (PO 4 ) 3 possesses better electrochemical performance.