Synthesis of NaNiF3 and its Composite with Multi-Walled Carbon Nanotubes as Cathode Materials for Aqueous Sodium-Ion Battery /

Abstract

Aqueous sodium-ion battery is a safe and efficient system for large-scale energy storage due to its low cost, abundant sodium supply, non-flammable aqueous neutral electrolyte, and quick charge-discharge performance. The usage of fluoride-based materials as electrode materials offers several advantages due to their high potential window and energy density. Exploring perovskite materials offers the benefit of a corner-sharing matrix structure, which aids in ion and electron transport. We used a simple and cost-effective method of precipitation and hydrothermal synthesis to create the perovskite-structured NaNiF3 and its composite with multi-walled carbon nanotubes (MWCNT). The synthesized material is characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller analysis (BET). Using 1 M Na2SO4 as electrolyte, cyclic voltammetry (CV), chronopotentiometry (CP), and electrochemical impedance spectroscopy (EIS) are used to evaluate the electrochemical performance of cathode material for aqueous sodium-ion battery. XRD confirms the perovskite structure of NaNiF3 and NaNiF3 // MWCNT, SEM shows the orthorhombic cube and cubical structure of NaNiF3 and NaNiF3 // MWCNT. The electrochemical results show that NaNiF3 and NaNiF3 // MWCNT have excellent performance with specific capacities of 33 mAh g-1 and 57 mAh g-1 at 0.1 A g-1 and shows 16 Wh kg-1 and 28 Wh kg-1 energy density respectively and excellent cyclic stability up to 500 cycles, indicating that NaNiF3 / MWCNT is a potential candidate as cathode material for aqueous sodium.