GaP-TiO₂-C Nanocomposite as High-Performance Sodium-Ion Batteries Anode

GaP-TiO₂-C composites with three different C concentrations are synthesized via a high-energy mechanical milling. The analysis of the structural characteristics of GaP-TiO₂-C using X-ray diffraction and high-resolution transmission electron microscopy reveals that the nanosized GaP and TiO₂ crystallites are uniformly distributed in the amorphous C matrix. The GaP-TiO₂-C(20%) composite exhibits a high Na storage capacity of 266 mAh g^-1 at the current density of 0.1 A g^-1 after 100 cycles, and the remarkable rate capability of 224 mAh g^-1 even at the higher current density of 10 A g^-1. In addition, the GaP-TiO₂-C(20%) composite presents great cycling performance and the capacity of 213 mAh g^-1 at the current density of 0.5 A g^-1 after 300 cycles. The outstanding cycling performance and rate capability of GaP-TiO₂-C(20%) anode can be attributed to the favorable morphology of GaP-TiO₂-C composite that accommodates large volume changes during cycling.