Design and Synthesis of Organic Radical Functionalized Vanadium Pentoxide Towards Long-Life Aqueous Zinc ion Batteries

Abstract

V2O5 cathode material has attracted considerable attention for rechargeable aqueous zinc-ion batteries (ZIBs) owing to the rich redox chemistry of vanadium. However, the cyclic performance of the V2O5 cathode is still hampered by the sluggish Zn2+ diffusion kinetics. Herein, we employed a facile “two-in-one” strategy to fabricate the organic radical functionalized V2O5 (V2O5-TEMPO) via selecting the 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) as the nitroxide monmer and riveting it onto the V2O5, and applied as the cathode of rechargeable aqueous zinc-ion batteries. Benefitting from the large specific area and the porous structure of V2O5-TEMPO cathode materials, the V2O5-TEMPO achieved large specific capacity of 327.4 mAh g-1 at 0.1 A g-1 and impressive cycling performance with capacity retention of 90.8 % after 5,500 cycles at 2.0 A g-1. In addition, the reversible storage mechanism of Zn2+ was further studied by kinetic analysis and density functional theory (DFT) calculations. This work provides the key insights into the design and fabrication of organic radical compounds-based cathode materials for constructing high-performance rechargeable aqueous multivalent ion batteries.