Enhanced zinc ions storage performance by calcium ion induction/ anchoring of vanadium-based nanobelts at low temperature

Low-cost, high abundance, environmentally friendly, and intrinsic safety endow the aqueous Zn ion batteries a bright prospect for large-scale energy storage. However, it is still challenging to find suitable cathode materials with excellent Zn2+ ion storage performance due to sluggish Zn2+ ions intercalation kinetics. Herein, we prepare the novel nanobelts as advanced cathode materials via a simple solution impregnation method. Firstly, the Ca2+ ions promote the conversion of vanadium-based materials from nanoparticles to nanobelts, and also act as a pillar to stabilize the structure of the vanadium-based material. Furthermore, the amorphous structure of the electrode also can be tuned by subsequent appropriate calcination, aiming to enhance Zn-storage performances. Thus, the cathode materials exhibit the superior electrochemical performances with a high-capacity retention rate of 93.75% at 0.5 A/g after 100 cycles and a capacity retention rate of 91.3% after 3000 cycles at 5 A/g. In addition, the flexible quasi-solid-state Zn ion batteries with Ca2+ ions pre-intercalated vanadium-based oxide as cathode is also investigated, and show stable electrochemical properties under bending states. With the cost-effective and green large-scale synthesis process, the outstanding electrochemical performance of cathode shed light on the rational design of novel cathodes for practical aqueous Zn ion batteries. (C) 2022 Elsevier Ltd. All rights reserved.