Ga 2 Te 3 -Based Composite Anodes for High-Performance Sodium-Ion Batteries.

Recently, metal chalcogenides have received considerable attention as prospective anode materials for sodium-ion batteries (SIBs) because of their high theoretical capacities based on their alloying or conversion reactions. Herein, we demonstrate a gallium(III) telluride (Ga 2 Te 3 )-based ternary composite (Ga 2 Te 3 -TiO 2 -C) synthesized via a simple high-energy ball mill as a great candidate SIB anode material for the first time. The electrochemical performance, as well as the phase transition mechanism of Ga 2 Te 3 during sodiation/desodiation, is investigated. Furthermore, the effect of C content on the performance of Ga 2 Te 3 -TiO 2 -C is studied using various electrochemical analyses. As a result, Ga 2 Te 3 -TiO 2 -C with an optimum carbon content of 10% (Ga 2 Te 3 -TiO 2 -C(10%)) exhibited a specific capacity of 437 mAh·g -1 after 300 cycles at 100 mA·g -1 and a high-rate capability (capacity retention of 96% at 10 A·g -1 relative to 0.1 A·g -1 ). The good electrochemical properties of Ga 2 Te 3 -TiO 2 -C(10%) benefited from the presence of the TiO 2 -C hybrid buffering matrix, which improved the mechanical integrity and electrical conductivity of the electrode. This research opens a new direction for the improvement of high-performance advanced SIB anodes with a simple synthesis process.