V2O3@C Microspheres as the High-Performance Cathode Materials for Advanced Aqueous Zinc-Ion Storage

Ultrasmall, Amorphous V2O3 Intimately Anchored on a Carbon Nanofiber Aerogel Toward High-Rate Zinc-Ion Batteries

When considered as a cathode candidate for aqueous Zn-ion batteries, V2O3 faces several problems, such as inherently unsuitable structure, fast structural degradation, and sluggish charge transport kinetics. In this paper, we report the synthesis of a V2O3 intimately coupled carbon aerogel by a controllable ion impregnation and solid-state reaction strategy using bacterial cellulose and ammonium metavanadate as raw materials. In this newly designed structure, the carbonized carbon fiber network provides fast ion and electron transport channels. More importantly, the cellulose aerogel functions as a dispersing and supporting skeleton to realize the particle size reduction, uniform distribution, and amorphous features of V2O3. These advantages work together to realize adequate electrochemical activation during the initial charging process and shorter transport distance and faster transport kinetics of Zn2+. The batteries based on the V2O3/CNF aerogel exhibit a high-rate performance and an excellent cycling stability. At a current density of 20 A g-1, the V2O3/CNF aerogel delivers a specific capacity of 159.8 mAh g-1, and it demonstrates an exceptionally long life span over 2000 cycles at 12 A g-1. Furthermore, the electrodes with active material loadings as high as 10 mg cm-2 still deliver appreciable specific capacities of 257 mAh g-1 at 0.1 A g-1.

Enhancing Interplanar Spacing in V2O3/V3O7 Heterostructures to Optimize Cathode Efficiency for Zn-Ion Batteries

The improvement of sophisticated cathode materials plays a major role in boosting the efficiency of Zn-ion batteries. These batteries have garnered considerable interest as a result of their excellent energy density and the promise of cost-effective solutions for energy storage. In this work, we present a novel approach to progress the electrochemical investigation of Zn-ion batteries by expanding the interplanar distance of layered hydrated V2O3/V3O7 heterostructure nanosheets. Electrochemical investigations were conducted to assess the effectiveness of the stacked hydrated V2O3/V3O7 heterostructure as a cathode component for Zn-ion batteries. The expanded interplanar space as a result of the introduction of water molecules facilitates the insertion/extraction of Zn ions, leading to significantly enhanced electrochemical characteristics. The layered hydrated V2O3/V3O7 heterostructure exhibited an impressive specific capacity of 330 mAh g-1 at a current density of 0.1 A g-1, maintaining a capacity retention of approximately 92.3% and a coulombic efficiency of 95.8% even after 2000 cycles.