Polyanion‐Type Na₃V₂(PO₄)₂F₃@rGO with High‐Voltage and Ultralong‐Life for Aqueous Zinc Ion Batteries

Abstract

Aqueous zinc ion batteries (AZIBs) have attracted much interest in the next generation of energy storage devices because of their elevated safety and inexpensive price. Polyanionic materials have been considered as underlying cathodes owing to the high voltage, large ionic channels and fast ionic kinetics. However, the low electronic conductivity limits their cycling stability and rate performance. Herein, mesoporous Na3V2(PO4)2F3 (N3VPF) nanocuboids with the size of 80–220 nm cladded by reduced graphene oxide (rGO) have been successfully prepared to form 3D composite (N3VPF@rGO) by a novel and fast microwave hydrothermal with subsequent calcination strategy. The enhanced conductivity, strengthened pseudocapacitive behaviors, enlarged DZn2+, and stable structure guarantee N3VPF@rGO with splendid Zn2+ storage performance, such as high capacity of 126.9 mAh g‐1 at 0.5 C (1 C = 128 mA g‐1), high redox potentials at 1.48/1.57 V, high rate capacity of 93.9 mAh g‐1 at 20 C (short charging time of 3 mins) and extreme cycling stability with capacity decay of 0.0074% per cycle after 5000 cycles at 15 C. The soft package batteries also present preeminent performance, demonstrating the practical application values. In situ X‐ray diffraction, ex situ transmission electron microscopy and X‐ray photoelectron spectroscopy reveal a reversible Zn2+ insertion/extraction mechanism.

Sodium‐Ion Substituted Water Molecule in Layered Vanadyl Phosphate Enhancing Electrochemical Kinetics and Stability of Zinc Ion Storage

“…The b-value of 0.5 represents the diffusion-controlled behavior, and b = 1 indicates the surface capacitive process. [45] The b-values of peaks 1-4 were determined to be 0.84, 1.00, 0.81, and 0.90 (Figure 4b), respectively, indicating that the electrochemical process of NaVOP is dominated by the pseudocapacitive behavior. In comparison, the cor-responding b-values of the VOP electrode (Figures S11 and S12, Supporting Information) is determined to be 0.82, 0.93, 0.78, and 0.88, respectively.…”

One-dimensional tunnel VO2(B) cathode materials for high-performance aqueous zinc ion batteries: a mini review of recent advances and future perspectives

“…2,3 In recent years, vanadium-based cathode materials have emerged as promising candidates for AZIBs. Among the various vanadium-based compounds explored for AZIBs, such as vanadium phosphates, 4,5 vanadium oxides, 6 vanadates, 7 vanadium sulfides, 8 and vanadium nitrides, 9 some have exhibited outstanding Zn 2+ storage capabilities. Notably, within vanadium oxide cathode materials, 1D tunnel VO 2 (B) cathode materials have garnered substantial research interest.…”

Ethylene Glycol Intercalation Engineered Interplanar Spacing and Redox Activity of Ammonium Vanadate Nanoflowers as a High-Performance Cathode for Aqueous Zinc–Ion Batteries

“…11−13 In recent years, most research on rechargeable cathode materials of AZIBs have focused on manganese-based compounds, 6,14−17 vanadium-based compounds, 18−20 Prussian blue analogues, 21,22 and polyanionic compounds. 23,24 Among these materials, layered vanadium-based compounds have been widely regarded as promising cathodes for AZIBs because of their high theoretical capacity and unique multielectron redox reaction based on the V element. 25,26 However, the narrow layer spacing of vanadium-based compounds generally leads to slow zinc ion transport.…”

“…In recent years, most research on rechargeable cathode materials of AZIBs have focused on manganese-based compounds, ,− vanadium-based compounds, − Prussian blue analogues, , and polyanionic compounds. , Among these materials, layered vanadium-based compounds have been widely regarded as promising cathodes for AZIBs because of their high theoretical capacity and unique multielectron redox reaction based on the V element. , However, the narrow layer spacing of vanadium-based compounds generally leads to slow zinc ion transport. A number of investigations have focused on modulating the interlayer spacing of vanadium-based materials using interlayer chemistry. ,, It is found that structured water and pillared ions are essential to improve the ion diffusion kinetics of vanadium-based compounds and accelerate charge transfer, so a series of cationic preinserted vanadium oxides have been developed as cathode materials for AZIBs. − Nevertheless, the introduction of heavy metal ions into the host structure of layered V-based materials may greatly reduce their theoretical capacity .…”