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Due to the low cost and abundance of sodium, sodium-ion batteries (SIBs) show great potential as energy storage devices. As far as the current research is concerned, cathode materials are still the bottleneck for boosting the performance of SIBs. O3-type layered NaNi 0.5 Mn 0.5 O 2 is considered as an important cathode material of SIBs, but its irreversible phase transition, poor stability in air, and sluggish kinetics usually lead to reduced capacity, poor rate performance and high cost for material storage, which largely limit the large-scale application. Herein, a remarkable O3-type layered material NaNi 0.5-x Mn 0.3 Ti 0.2 Zr x O 2 (NaNMTZ, x = 0.02, 0.05), with stable phase structure has been synthesized by the solid-phase method. The partial substitution of electrochemical inactive Ti/Zr brings about higher electronic delocalization and entropy of mixing leading to enhanced structural stability. In addition, the enlarged interlayer spacing and good conductivity contribute to better rate capability. The micro-nano structure leads to faster Na+ diffusion rates and shorter diffusion paths for both ions and electrons. Therefore, NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 exhibits an initial reversible capacity of 141.4 mAh g−1 with a coulombic efficiency of 98.8% and remarkable capacity retention of 70% after 200 cycles at 0.05C, presenting better electrochemistry performance than the conventional NaNi 0.5 Mn 0.5 O 2. This study provides a new angle to design high capacity cathode materials with high rate capability and cycling stability through crystal lattice modulation. Image 1 • A remarkable O3-type layered NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 is designed as cathode material for sodium ion batteries. • The structural stability and rate performance of NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 are superior. • The higher electronic delocalization and better conductivity of NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 are provided. • The difference value about entropy of mixing between NaNi 0.5 Mn 0.5 and NaNi 0.45 Mn 0.3 Ti 0.2 Zr 0.05 O 2 is calculated. • The enlarged interlayer spacing and micro-nano structure contribute to the high rate capability. [ABSTRACT FROM AUTHOR]