Three-Dimensional Fast Na-Ion Transport in Sodium Titanate Nanoarchitectures via Engineering of Oxygen Vacancies and Bismuth Substitution
- Jun Mei*Jun Mei*Email: [email protected] (J.M.).Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, AustraliaSchool of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, AustraliaMore by Jun Mei,
- Tiantian WangTiantian WangSchool of Mechanical, Medical and Process Engineering, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, AustraliaState Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, ChinaUniversity of Chinese Academy of Sciences, Beijing 100049, ChinaMore by Tiantian Wang,
- Dongchen Qi ,
- Jianjun Liu ,
- Ting LiaoTing LiaoCentre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, AustraliaSchool of Mechanical, Medical and Process Engineering, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, AustraliaMore by Ting Liao,
- Yusuke YamauchiYusuke YamauchiAustralian Institute for Bioengineering and Nanotechnology and School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, AustraliaJST-ERATO Yamauchi Materials Space-Tectonics and International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, JapanMore by Yusuke Yamauchi, and
- Ziqi Sun*
Layered sodium titanates (NTO), one of the most promising anode materials for advanced sodium-ion batteries (SIBs), feature high theoretical capacity and no serious safety concerns. The pristine NTO electrode, however, has unfavorable Na+ transport kinetics, due to the dominant two-dimensional (2D) Na-ion transport channels within the crystal along the low energy barrier octahedron layers, which impedes the practical application of this class of potential materials. Herein, an interesting concept of opening three-dimensional (3D) fast ion transport channels within the intrinsic NTO frameworks is proposed to enhance the electrochemical performance through a combination of oxygen vacancy generation and cation substitution strategies, by which the interlayer spacing of the NTO frameworks is expanded for fast 3D Na-ion transport. It is evidenced that the oxygen-deficient and bismuth-substituted HBNTO (BixNa2–xTi3Oy, 0 < x < 2, 0 < y < 7, HBNTO) exhibits obvious enhancements on the reversible capacity (∼145% enhancement at 20 mAh g–1 compared with NTO), the rate capability (∼200% enhancement at 500 mAh g–1 compared with NTO), and the cycling stability (∼210% enhancement of retention capacity after 150 cycles at 20 mAh g–1 compared with NTO). The molecular dynamic simulations and theoretical calculations demonstrate that the enhanced performance of HBNTO is contributed by the multiplied sodium diffusion pathways and the increased ion migration rates with the successful opening of 3D internal ion transport channels. This work demonstrates the effectiveness of the strategies in opening the 3D intercrystal ion transport channels for boosting the electrochemical performance of SIBs.
This article has not yet been cited by other publications.