Improved lithium storage performance of NaTi2(PO4)3/C composite connected by carbon nanotubes
Abstract NaTi2(PO4)3/C (NC) composites decorated by carbon nanotubes (CNTs) were prepared via a sol-gel way, and employed as anode in aqueous lithium ion batteries. An effective conductive network was obtained by decoration of CNTs, which can interconnect NC particles. CNTs decoration has no obvious effect on lattice structure for NaTi2(PO4)3, and can enhance electrochemical properties for NC. Moreover, NC decorated by CNTs with optimal content of 8.8% (NC-CNTs-10) exhibits the highest electrochemical properties. NC-CNTs-10 delivers the discharge capacity of 96.4, 93.7, and 74.2 mAh g−1 at 0.5, 3, and 15C, respectively, with increase of 2.7, 15.1, and 38.2 mAh g−1 compared with NC. In addition, NC-CNTs-10 shows excellent cycling performance. Capacity retention for NC-CNTs-10 can reach 91.2% after 1000 cycles at a rate of 4C, 16.7% larger than that of pristine NC. Our study reveals that CNTs decoration is a simple way to raise electrochemical properties for NaTi2(PO4)3/C in aqueous lithium ion batteries.