Abstract
The oxalate-phosphate polyanion-mixed cathode materials are promising for sodium-ion batteries (SIBs) due to their unique open-framework structures and high voltage property. However, materials of this type generally contain crystal water molecules in the lattice frameworks, which may affect their energy storage properties. This work aims to disclose the impacts of crystal water on physiochemical and electrochemical properties of Na 2 (VO) 2 (HPO 4 ) 2 (C 2 O 4 )•2H 2 O (NVPC-W). It shows that the water molecules can be eliminated by vacuum drying at 150°C. The elimination of water molecules does not change the crystal phase of the material, while the obtained Na 2 (VO) 2 (HPO 4 ) 2 (C 2 O 4 ) (NVPC) exhibits significant improvements in cycling stability, Coulombic efficiency, as well as rate performances. Kinetics analysis indicates that the existence of lattice water molecules hinders sodium-ion diffusion and promotes the degradation of electrodes. We believe the findings can help to develop high-performance cathode materials. The crystal water eliminated Na 2 (VO) 2 (HPO 4 ) 2 (C 2 O 4 ) material exhibits significant improvements in cycling stability, Coulombic efficiency, as well as rate performances. Kinetics analysis indicates that the existence of lattice water molecules hinders sodium-ion diffusion and promotes the degradation of electrodes.
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.