Yeast biological template triggers strain effects and constructs multielectron reaction Na2.25Ti0.75V1.25(PO4)3 for high-performance sodium-ions batteries

Sodium super ion conductor (NASICON) structure materials such as Na 3 V 2 (PO 4 ) 3 (NVP) are suitable cathodes for Sodium-ion batteries (SIBs) due to their open three-dimensional structure that can provide fast Na + migration channels. However, low inherent conductivity and capacity restrict the application of NVP. In this paper, NASICON-structured Na 2.25 V 1.25 Ti 0.75 (PO 4 ) 3 @Y (NT 0.75 VP@Y) constructed by yeast with the biological template method is successfully synthesized. Theoretical calculations show that the spherical structure of bio-derived carbon formed after calcination produces a local compressive strain that leads to a uniform distribution of electronic states and stronger adsorption of Na + and NaClO 4 , thus enhancing the electronic and ionic conductivities of the material. NT 0.75 VP@Y exhibits a discharge specific capacity of 135 mAh g −1 at 0.2 C and a capacity retention rate of 94.8 % after 500 cycles. Finally, the full cell and the pouch cell are successfully assembled to verify the practicality of NT 0.75 VP@Y. This paper provides a simple, low-cost, and environmentally friendly way to synthesize high-performance cathode materials for SIBs.