3D Porous NaTi2(PO4)(3) with Long Life, Superior Rate, and Low-Temperature Properties

摘要

Reticular 3D porous NaTi2(PO4)(3) thin films decorated with reduced graphene oxide (NTP@rGO) on a nickel foam substrate are synthesized by electrostatic spray deposition technique. The interconnected pore networks and highly conductive carbon frameworks not only facilitate the kinetics of sodium-ion diffusion but also provide abundant reaction interfaces. The NTP@rGO electrode shows superb rate performance with a charge capacity of 109.4 mAh g(-1) at 100 C, i.e., 96.8% retention of its capacity at 0.5 C. After 2500 cycles at 20 C, the reversible capacity still reaches 93.1 mAh g(-1) with a very slow capacity decay of 0.0045% per cycle. Even at -10 degrees C, NTP@rGO still delivers 98 mAh g(-1) at 50 C and 92.5 mAh g(-1) at 100 C. Such a composite anode combines the advantages of batteries and supercapacitors, showing great potential applicability for high-energy and high-power sodium-ion storage.