Abstract
Li6-xZr2-xAxO7 (A = Nb; Ta) system with 0 < x < 0.30 is synthesized by glycine-nitrate method. Boundaries of solid solutions based on monoclinic Li6Zr2O7 are determined; temperature (200–600 °C) and concentration dependences of conductivity are investigated. It is shown that monoclinic Li6Zr2O7 exhibits better transport properties compared to its triclinic modification. Li5.8Zr1.8Nb(Ta)0.2O7 solid solutions have a higher lithium-cation conductivity at 300 °C compared to solid electrolytes based on other lithium zirconates due the “open” structure of monoclinic Li6Zr2O7 and a high solubility of the doping cations.
Highlights
Lithium zirconates are a subject of wide-ranging studies during the last years due to the wide range of their practical applications
Temperature (300–600 ◦C) and concentration dependences of conductivity have been studied for the synthesized materials, their transport properties have been compared with the properties of other lithium zirconate-based solid electrolytes
Solid solutions of Li5.80Zr1.80Nb(Ta)0.20O7 composition have a higher lithium-cation conductivity at 300 ◦C compared to solid electrolytes based on other lithium zirconates and to Li6Zr2O7-based solid solutions yielded by doping Li6Zr2O7 with double- or triple-charged cations
Summary
Lithium zirconates are a subject of wide-ranging studies during the last years due to the wide range of their practical applications. A more considerable conductivity growth is observed when Zr4+ ions are substituted for pentavalent cations (Nb5+ or Ta5+) with the positive charge excess compensation by lithium vacancies. The work [23], investigates only two compositions of solid electrolytes: Li5.85Zr1.85A0.15O7 (A = Nb, Ta) Such high conductivity values obtained in the initial studies give reason to extend study of the conductivity of Li6Zr2O7-based solid solutions in Li6-xZr2-xNbxO7 and Li6-xZr2-xTaxO7 systems in the wide concentration region. The present paper investigates the effect the concentration of pentavalent doping cations in Li6-xZr2-xAxO7 (A = Nb, Ta) systems has on the lithium-cation conductivity of Li6Zr2O7. It is assumed that when A5+ ions replace Zr4+, the compensation of the charge imbalance by lithium vacancies can be described as
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
