Tuning electrochemical performance of Fe hyper‐doped TiO ₂ anodes for Na‐ion batteries

Abstract The development of TiO 2 as an anode for Na‐ion batteries (SIBs) is hindered by two major challenges: low electronic conductivity and sluggish sodium‐ion diffusion kinetics. Although defect engineering methods such as heteroatom doping and the introduction of oxygen vacancies have been explored to enhance these properties, the synergistic effect of Fe‐hyperdoping in TiO 2 and introducing non‐equilibrium oxygen vacancies (under externally applied electric field) remains unexplored. This study investigates the impact of hyperdoping 10 at.% Fe in TiO 2 , utilizing the flash sintering technique, to develop a high‐performance anode material for SIBs. The electrochemical performance of flash‐sintered‐doped TiO 2 is systematically compared to that of conventionally sintered doped TiO 2 , demonstrating significant improvements in conductivity and sodium‐ion storage capacity. The findings provide new insights into defect engineering strategies for next‐generation SIB anodes.