Metal Doped Ammonium Vanadium Oxide Cathode with Exceptionally Discharge Capacity for Sodium-Ion Battery Fabrication

Abstract

Sodium ion battery, has attracted great attention to the energy storage system for its low cost and uniform abundant resources in the earth crust and also for its similar chemical property to lithium. Basically, sodium-ion has larger ionic size than lithium needs a wider open framework to accumulate the larger ion during the intercalation-deintercalation process. Herein, we demonstrate one-dimension ammonium vanadium oxide (NH 4 V 4 O 10 ) material as suitable cathode materials for Na-ion storage. The layered structured ammonium vanadium oxide is prepared by the simple hydrothermal process. The elongation of NH 4 V 4 O 10 nano-belts towards c-axis and minimum growth towards b-axis i.e., [0k0] results in a faster Na-ion transport and provide a high reversible capacity. Here, we improved the capacity by a metal oxide (Al, Ni, and Zr) doping on NH 4 V 4 O 10 . Among all, zirconium-doped NH 4 V 4 O 10 showed best electrochemical performance. We further optimized the zirconium doping concentration on NH 4 V 4 O 10 . The best electrochemical performance was obtained by 3.33-mole% zirconium doping on vanadium side of NH 4 V 4 O 10 . The doped Zr- NH 4 V 4 O 10 showed high discharge capacity of 342 mAh g -1 at 200 mA g -1 current density and even at the higher current rate of 500 mA g -1 current rate it exhibited the high discharge capacity of 185 mAh g -1 with 81 % capacity retention after 50 cycles.