Construction of porous biphasic ZnTiO3 rods as anode materials for high-performance Li-ion batteries driven by a hybrid Li storage mechanism

Abstract

Titanium-based oxide materials have become a potential candidate anode material for power LIBs due to its good structural stability and high safety performance. However, poor conductivity of titanium-based anode materials hinders their practical application. To solve this issue, porous ZnTiO3 rods and ZnTiO3/polytopamine (PDA) composites with excellent electrochemical properties were synthesized by solvothermal method and simple chemical polymerization in this work. The diameter of ZnTiO3 and ZnTiO3/PDA rods is around 800 nm. The ex-situ XRD and electrochemical characterization confirm that ZnTiO3 has intercalation, conversion and alloying reaction mechanism, resulting in higher capacity than most titanium-based anode materials. The ZnTiO3/PDA (6.2 wt%) anode possesses excellent cycling stability, which can provide a specific charge capacity of 467.1 mAh·g−1 after 500 cycles at 1000 mA·g−1. Moreover, after cycling, most of the ZnTiO3/PDA (6.2 wt%) still maintained the morphology of complete porous rods, indicating moderate PDA coating can significantly mitigate the volume change during the electrochemical reaction process and improve electrochemical properties. The EIS results demonstrate PDA coating can enhance the electrochemical reaction activity of ZnTiO3 materials. Therefore, the PDA coating is an effective approach to enhance the electrochemical performance of titanium-based anode materials.