Carbon nanotube linked NaTi2(PO4)3/C composite with three-dimensional conductive network as superior electrode for sodium ion battery

NASICON-type NaTi2(PO4)3 is regarded as promising electrode material due to stable structure and large three-dimensional channels. NaTi2(PO4)3/C composite with carbon nanotubes modification (NTP-CNTs) has been synthesized via sol-gel approach and employed for sodium ion battery. Carbon nanotubes have no distinct influence on crystal form of NaTi2(PO4)3. NTP-CNTs displays distinguished cycling and rate performance. NTP-CNTs delivers discharge capacity of 246.2, 220.2, and 183.5 mAh g−1 at 0.04, 0.1, and 2 A g−1, respectively, 60.4, 57.4, and 70.9 mAh g−1 larger than those of bare NTP. Moreover, discharge capacities of NTP and NTP-CNTs are 121.6 and 169.3 mAh g−1 after 500 cycles at 1 A g−1, respectively. Outstanding electrochemical property may be due to that carbon nanotubes enhance electrical conductivity and dispersibility of NTP-CNTs. Decentralized NaTi2(PO4)3 particles and carbon nanotubes corporately form three-dimensional conductive network with good dispersion, which is beneficial to accelerating the migration of sodium ions and electrons.