Synergic and coupling effect between SnO2 nanoparticles and hierarchical AlV3O9 microspheres toward emerging electrode materials for lithium-ion battery devices

Abstract

The rational design of proficient and durable active materials is an important task for rechargeable Li-ion batteries. Herein, AlV₃O₉/SnO₂ binary nanocomposites (AVS) were fabricated by a low-temperature and short-time PEG-assisted hydrothermal method combined with subsequent calcination. The as-prepapred 3D hierarchical flower-shaped AVS micro/nanosphere composites showed a more specific capacity than those of pristine AlV₃O₉ (AV) structures due to the coupling effect of two different energy-storage materials. Therefore, SnO₂ with a preferable conductivity was equipped with facile electron transport among AlV₃O₉ and electrode layers. Notably, we followed the changes of the SnO₂ content (5, 10, 20 wt%) to investigate the cycle stability, rate capability, and Couloumbic efficiency during the battery testing. As a positive electrode for a Li-ion battery, the cell with AVS nanocomposites including 20 wt% SnO₂ was able to deliver a high specific capacity of 611.02 mA h g⁻¹ at a current rate of 0.1C, which represented an upgrade over pristine AlV₃O₉ (233.05 mA h g⁻¹). The assembled battery with AVS flower-shaped nanocomposites could be steadily cycled for 75 times at a current rate of 1C with an efficiency as high as ∼99%. Therefore, AlV₃O₉/SnO₂ nanocomposites offer considerable promise to realize an operationally attractive Li-ion battery electrode.