Exploring the electrochemical properties of Na2S -V2O5-P2O5 glass-ceramic nanocomposites as a cathode for magnesium-ion batteries

High charge density of Mg yields the sluggish kinetic of Mg2+ insertion/extraction in the host lattice, this is a main difficulty to realize the commercial applications. As an attempt to overcome this challenge, a glass sample (NSVP) was prepared following the molar ratio (13.5 Na2S - 32.5 V2O5-54 P2O5) mol% using the melt-quenching process in addition to its corresponding glass-ceramic nanocomposites. All samples were employed in a fully assembled Mg ion coin cell at both room temperature and 55 degrees C. The CV, CA, GCD and EIS were reported for all the present samples. The diffusion coefficient of Mg ions-10-16 indicates that Mg ion diffusion in the prepared host structures is moderately favorable. The 12 h sample achieved the best electrochemical performance at both temperatures (e.g., the highest initial capacity-86 mAh g-1, energy density-11 Wh Kg-1 at 55 degrees C and high stability). Its coulombic efficiency was 78% at 55 degrees C after 100 cycles. This can be due to smaller crystalline size (42 nm) and/or due to the flexible structure of beta-VOPO4 having corner-sharing VO5 pyramids along with PO4 tetrahedra, similar to VO5F octahedra and PO4 tetrahedra in Na3V2O2F(PO4)2. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The glass sample NSVP and its glass-ceramic nanocomposites exhibited excellent electrochemical performance in Mg ion coin cells, with the 12-hour processed sample showing the best results at 55 degrees Celsius.