Anthraquinone, C14H6O4Na2-CNT, Anode material, Ether-based electrolyte, Sodium-ion batteries, Renewable energy sources, TJ807-830, Ecology, QH540-549.5

Organic materials, especially the carbonyl compounds, are promising anode materials for room temperature sodium-ion batteries owing to their high reversible capacity, structural diversity as well as eco-friendly synthesis from bio-mass. Herein, we report a novel anthraquinone derivative, C14H6O4Na2 composited with carbon nanotube (C14H6O4Na2-CNT), used as an anode material for sodium-ion batteries in ether-based electrolyte. The C14H6O4Na2-CNT electrode delivers a reversible capacity of 173 mAh g−1 and an ultra-high initial Coulombic efficiency of 98% at the rate of 0.1 C. The capacity retention is 82% after 50 cycles at 0.2 C and a good rate capability is displayed at 2 C. Furthermore, the average Na insertion voltage of 1.27 V vs. Na+/Na makes it a unique and safety battery material, which would avoid Na plating and formation of solid electrolyte interface. Our contribution provides new insights for designing developed organic anode materials with high initial Coulombic efficiency and improved safety capability for sodium-ion batteries.