Electrochemical performance of novel Li3V2(PO4)(3) glass-ceramic nanocomposites as electrodes for energy storage devices

摘要

The novel Li3V2(PO4)(3) glass-ceramic nanocomposites were synthesized and investigated as electrodes for energy storage devices. They were fabricated by heat treatment (HT) of 37.5Li(2)O-25V(2)O(5)-37.5P(2)O(5) mol% glass at 450 A degrees C for different times in the air. XRD, SEM, and electrochemical methods were used to study the effect of HT time on the nanostructure and electrochemical performance for Li3V2(PO4)(3) glass-ceramic nanocomposites electrodes. XRD patterns showed forming Li3V2(PO4)(3) NASICON type with monoclinic structure. The crystalline sizes were found to be in the range of 32-56 nm. SEM morphologies exhibited non-uniform grains and changed with variation of HT time. The electrochemical performance of Li3V2(PO4)(3) glass-ceramic nanocomposites was investigated by using galvanostatic charge/discharge methods, cyclic voltammetry, and electrochemical impedance spectroscopy in 1 M H2SO4 aqueous electrolyte. The glass-ceramic nanocomposites annealed for 4 h, which had a lower crystalline size, exhibited the best electrochemical performance with a specific capacity of 116.4 F g(-1) at 0.5 A g(-1). Small crystalline size supported the lithium ion mobility in the electrode by decreasing the ion diffusion pathway. Therefore, the Li3V2(PO4)(3) glass-ceramic nanocomposites can be promising candidates for large-scale industrial applications in high-performance energy storage devices.