Abstract
As a safe, low-voltage anode material, in recent years, Na2Ti3O7 has become regarded as a highly alternative negative material for high energy room-temperature sodium ion batteries. However, its poor ion and electron conductivity produces very poor electrochemical performance of Na2Ti3O7, therefore greatly limiting its practical application in future scalable utilization. We report here a self-doping of Ti3+ into the Na2Ti3O7 electrode material, through a very simple post heat-treatment process, that is, annealing the Na2Ti3O7 precursor at an argon atmosphere containing 5% H2. By XPS characterization, it is confirmed that Ti3+ is successfully doped into Na2Ti3O7. Benefiting from this self-doped Ti3+ with larger ionic radius and better electronic conductivity, the obtained Na2Ti3O7 demonstrates improved electron conductivity and ion diffusion properties. Combined with a carbon coating, this self-doped Na2Ti3O7 electrode material exhibits superior electrochemical performance to that of non-doped electrode, e.g., this Na2Ti3O7 sample could delivers a specific capacity of 187.8 and 51.9 mAh g−1 from 0.1C to 10C at various rate of discharge, respectively. When recycled back to 0.1C, it can still reach 153 mAh g−1. Compared with numerous reported nanoscale means, we believe this approach is practical and productive, and may extend to other ti-based electrode materials.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.