@article{Guo2026, 
author = {Qingling Guo and Lina Yang and Nazir Ahmad and Shanshan Ye and Yuting Ruan and Yulian Hu and Wenxiu He and Liang Shi and Yongqiang Zhang and Jianguo Lu and Genqiang Zhang},
title = {High-entropy lattice pinning effect enables long lifespan and air stability in O3-type sodium-ion battery cathodes},
year = {2026},
journal = {Nano Research Energy},
volume = {5},
pages = {e9120231},
keywords = {high entropy, sodium ion batteries, cathode materials, O3 phase material, suppressing complex phase transition},
url = {https://www.sciopen.com/article/10.26599/NRE.2026.9120231},
doi = {10.26599/NRE.2026.9120231},
abstract = {O3-type NaNi0.4Fe0.2Mn0.4O2 cathodes suffer from harmful phase transitions and large volume strains, leading to sluggish Na+ kinetics and poor cyclability. To address these issues, we propose dual-site doping via a high-entropy strategy, O3-Na0.96Ca0.02Ni0.27Fe0.2Mn0.35Al0.02Cu0.1Ti0.05O2 (NCNFMACTO) cathode. Based on the Rietveld refinement of X-ray diffraction (XRD) data and DFT calculations, it is inferred that Ca2+ doping occupies the sodium sites, generating an “anchoring effect” that stabilizes the transition metal layer during the desodiation process. Concurrently, doping the transition-metal layer with multi-principal elements (Al, Cu, Ti) induces a lattice-regulating effect. This reinforces TM-O covalency and impedes slab gliding, thereby suppressing detrimental phase evolution and minimizing volume change. As a result, the material undergoes a reversible O3-P3-O3 phase transition with only 1.1% volumetric strain, significantly enhancing Na+ diffusion kinetics. The doped cathode exhibits remarkable cycling stability (91% capacity retention after 200 cycles at 1C and 80.1% capacity retention after 1000 cycles at 5C) and excellent air stability. Moreover, the NCNFMACTO//HC full cell maintains 85.2% capacity retention over 400 cycles at 1C. The full cell demonstrates an excellent energy density of 264.87 Wh·kg–1 at 44.42 W·kg–1, fully demonstrating its feasibility. This work provides key insights for designing high-stability sodium-layered oxide cathodes.}
}