Controlled Synthesis of NaV6O15 Nanorods with High Reversible Capacity and Excellent Cycling Stability

In this work, we demonstrate an effective method to improve capacitive performance of NaV6O15 intrinsically by annealing. NaV6O15 nanorods (NRs) prepared by a simple annealing treatment exhibit significantly improved electrochemical performance compared with the untreated NaV6O15 electrode, and yield a high specific capacitance (402.8 F/g at 300 mA/g). Furthermore, the annealing treated nanorods show excellent rate capability and cycling stability (ca. 80% capacitance retention after 1000 cycles at a scan rate of 100 m V/s). Our results have confirmed that the annealing treatment has great influence on the capacitive performance of NaV6O15, which may be attributed to the intrinsic three dimensional (3D) tunneled structures of NaV6O15, and NR morphology. These findings may further broaden the application of NaV6O15-based materials for high performance supercapacitors (SCs), aqueous rechargeable lithium batteries and Li-ion capacitors.