LiNaTi3O7作为锂离子电池负极材料的合成及电化学性能研究

Lithium titanate (Li 2 Ti 3 O 7 ) exhibits high ionic conductivity, but it faces commercialization challenges due to its high synthesis temperature (> 1100 ℃) and high cost. Sodium titanate (Na 2 Ti 3 O 7 ) has been explored as a stable anode material for aqueous sodium-ion batteries (SIBs) and is considered a potential alternative to Li 2 Ti 3 O 7 . However, its wide bandgap energy (3.7 eV) limits both electronic conductivity and practical applications. In this study, LiNaTi 3 O 7 was synthesized through a mechano-chemical method using Li 2 CO 3 , Na 2 CO 3 , and TiO 2 as precursors. The material was calcined at various temperatures (700–900 ℃) for 12 h to optimize crystallinity and electrochemical performance. The phase purity and crystallinity were verified via X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. Notably, the sample calcined at 800 ℃ for 12 h showed the sharpest diffraction peaks and minimal particle agglomeration. The electrochemical tests of LNTO-800–12 revealed a stable voltage plateau at 1.3 V, an initial discharge capacity of 141.7 mAh/g, and capacity retention of 93.6% after 120 cycles at 50 mA/g. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests demonstrated excellent reversibility and low charge transfer resistance (167 Ω). These findings demonstrate that LiNaTi 3 O 7 is a promising high-performance, cost-effective anode material for LIBs.