Novel synergistic 0.9LiMn(0.9)Fe(0.1)PO(4)center dot 0.1Na(3)V(2)(PO4)(2)F-3/C nano-hybrid cathode with enhanced electrochemical performance for lithium-ion batteries

摘要

The nanostructured 0.9LiMn(0.9)Fe(0.1)PO(4.0)center dot 0.1Na(3)V(2)(PO4)(2)F-3/C composites are successfully synthesized by a facile solvothermal method followed by mechanical activation and subsequent carbonthermal reduction process. Behaviours of bi-phase co-existence and element mutual-substitution have been investigated by XRD, TEM/EDX and FTIR. The result shows that the composites have dual phase boundaries including the semi-coherent phase interface and incoherent phase interface, as well as the advantage of Na3V2(PO4)(2)F-3 acting as ionic conductor. Due to the multifunctional phase and (Mn,Fe)-V mutual doping as well as nano-carbon continual conducting network, enhanced Li+ migration and charge transfer of nano-hybrid is obtained. Compared with pristine one, the 0.9LiMn(0.9)Fe(0.1)PO(4)center dot 0.1Na(3)V(2)(PO4)(2)F-3/C composites exhibit high rate capability and cycling ability, showing 125.5,106.4 mAh g(-1) at 1.0 C, 3.0 C at room temperature, respectively, with high capacity retention up to 93.9% after 600th at 2 C. (C) 2015 Elsevier B.V. All rights reserved.