Complexant-facilitated assembly of NiTiO3 nanoparticles into microbars for high-performance lithium-ion battery anode

Abstract

Nickel titanate (NiTiO₃) nanostructured materials have gained extensive attention in the field of lithium-ion batteries (LIBs) due to their high theoretical capacity and low cost. However, NiTiO₃ exhibits low conductivity and significant volume changes during cycling, resulting in capacity decay and poor cycling stability. Herein, we propose a feasible strategy to enhance the cycling performance of NiTiO₃ nanostructures by adjusting their morphology. By manipulating the choice of solvent employed in the synthetic process, we obtain NiTiO₃ microbars (NTO MBs) through self-assembly of NiTiO₃ nanoparticles (NTO NPs). When utilized as an anode material in LIBs, NTO MBs exhibit a capacity of 410 mAh g⁻¹ after 200 cycles at 100 mA g⁻¹, surpassing that of NTO NPs (212 mAh g⁻¹). The improved performance of NTO MBs is attributed to their unique porous bar-like structure, composed of numerous NPs, which provides a substantial storage space for Li⁺ ions owing to its larger specific surface area. Additionally, the porous structure accelerates the diffusion of Li⁺ ions and electron transfer. To gain a profound understanding of the enhanced performance through morphology adjustment, we conduct a comprehensive investigation on the growth mechanism of NTO MBs. This work provides valuable insights into the mechanism governing the morphology control of NTO MBs, facilitating the rational design and synthesis of tailored materials with enhanced performance for LIBs.