Improvement of the electrochemical properties of Na2MnPO4F by dual modification of Na3V2(PO4)2F3 and Ti3C2-CQDs

The effects of the two materials, Ti3C2-CQDs and Na3V2(PO4)(2)F-3, on the electrochemical properties of Na2MnPO4F were systematically investigated by double modification of Na2MnPO4F by spray drying method combined with high-temperature calcination. Firstly, different ratios of xNa(2)MnPO(4)F-(1-x)Na3V2(PO4)(2)F-3 materials were synthesized and discussed to obtain 0.6Na(2)MnPO(4)F-0.4Na(3)V(2)(PO4)(2)F-3 material as optimal ratio. Ti3C2-CQDs were added on this basis, and electrochemical tests were performed at the same time. The initial discharge-specific capacity of 0.6Na(2)MnPO(4)F-0.4Na(3)V(2)(PO4)(2)F-3/Ti3C2-CQDs was 137.4 mAh-g(-1), indicating that Ti3C2-CQDs can improve the electronic conductivity as well as the ion diffusion rate of the material and the capacity retention rate. Na3V2(PO4)(2)F(3 )can effectively inhibit the Jahn-Teller effect, enhance the stability of the material structure, and improve the electrochemical activity of the material. The synergistic modification leads to a double enhancement of the electrochemical performance of Na2MnPO4F. It hopes that the findings can provide ideas for improving the electrochemical properties of polyionic compounds.