Abstract
We investigate phase stability and ionic transport mechanisms in two recently discovered superionic conductors, Li3OX (X = Cl, Br), from first principles. These compounds, which have an antiperovskite crystal structure, have potential applications as solid electrolytes in Li-ion batteries. We identify a low-barrier three-atom hop mechanism involving Li interstitial dumbbells. This hop mechanism is facile within the (001) crystallographic planes of the perovskite crystal structure and is evidence for the occurrence of concerted motion, similar to ionic transport in other solid electrolytes. Our first-principles analysis of phase stability predicts that antiperovskite Li3OCl (Li3OBr) is metastable relative to Li2O and LiCl (LiBr) at room temperature. We also find that although the band gap of Li3OCl exceeds 5 eV, the metastable antiperovskite becomes susceptible to decomposition into Li2O2, LiCl and LiClO4 above an applied voltage of 2.5 V, suggesting that these compounds are most suited for low-voltage Li ...
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.