(1.The State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China) (2.Research Institute of Chemical Defense, Academy of Military Sciences PLA China, Beijing 102205, China)
In recent years, titanium dioxide (TiO2) has attracted a lot of attention as the active anode material in sodium rechargeable battery (NIB) due to its low cost and stability. However, in practice the intrinsically slow transport kinetics of electrons in TiO2 prevent optimal electrochemical performance. Here, we prepared a hierarchical porous TiO2/C hybrid with oxygen vacancies through a simple carbonization of a Na+ controlled Ti-alginate self-crosslinking for the high-performance anode of sodium-ion batteries. Owing to the combination of hierarchical porous carbon matrix and the TiO2 nano-particles, the TiO2/C provided a capacity of 180.4 mAh·g-1 after 300 cycles at a current density of 100 mA·g-1, and delivered an excellent reversible capacity of 102.3 mAh·g-1 after 1000 cycles even at a higher current density of 1000 mA·g-1. Such good electrochemical performance has demonstrated the great potential of TiO2/C hybrids used as anodes for NIB.