Molten salt electrochemical synthesis of sodium titanates as high performance anode materials for sodium ion batteries

Abstract

Sodium ion batteries are attractive alternatives to lithium ion batteries for stationary energy storage technology, and titanates are considered as promising anode materials for sodium ion batteries. Herein, a series of sodium titanates were synthesized via a simple, fast and controllable electrochemical route from solid TiO₂ in molten salts of NaF–NaCl–NaI. For the first time, the as-prepared Na_0.23TiO₂ and Na_0.46TiO₂ were utilized as anode materials for sodium ion batteries, with a sodium storage capacity of 185 mA h g⁻¹ and 215 mA h g⁻¹ after 200 cycles, respectively. High rate and long term tests indicated the excellent cycle performance due to the formation of a 3D porous electrode structure during the long term charge/discharge processes.