RESUMEN
This paper reports the synthesis and characterization of hydrated vanadium oxide (VOH) and chemically preintercalated polyanilines in VOH, labeled as PAVO-H as the cathode material for aqueous zinc-ion batteries. Synthesized PAVO-H has a high surface area and rod-shaped morphology. PAVO-H has an increased interlayer distance of 13.36 Å. PAVO-H offers high specific capacities of 330 and 225 mAh g-1 at 50 mA g-1 and 4 A g-1 of current densities, respectively, with a 92% capacity retention rate of over 3000 cycles. The preintercalation of polyaniline is likely to catalyze the redox reaction and facilitate and simplify transport kinetics. It is also possible that the preintercalation of polyaniline permits the insertion of large hydrated Zn ions and reduces the formation of zinc basic salts.
RESUMEN
Hydrated V2O5 with unique physical and chemical characteristics has been widely used in various function devices, including solar cells, catalysts, electrochromic windows, supercapacitors, and batteries. Recently, it has attracted extensive attention because of the enormous potential for the high-performance aqueous zinc ion battery cathode. Although great progress has been made in developing applications of hydrated V2O5, little research focuses on improving current synthesis methods, which have disadvantages of massive energy consumption, tedious reaction time, and/or low efficiency. Herein, an improved synthesis method is developed for hydrated V2O5 nanoflakes according to the phenomenon that the reactions between V2O5 and peroxide can be dramatically accelerated with low-temperature heating. Porous hydrated V2O5 nanoflake gel was obtained from cheap raw materials at 40 °C in 30 min. It shows a high specific capacity, of 346.6 mAh/g, at 0.1 A/g; retains 55.2% of that at 20 A/g; and retains a specific capacity of 221.0 mAh/g after 1800 charging/discharging cycles at 1 A/g as an aqueous zinc ion battery cathode material. This work provides a highly facile and rapid synthesis method for hydrated V2O5, which may favor its applications in energy storage and other functional devices.
RESUMEN
Hydrated vanadium pentoxide (VO) cathodes with two-dimensional bilayer structures hold great potential for advanced aqueous Zn-ion batteries (ZIBs) construction, but their further application is impeded by the poor cycling stability. Herein, to address this issue and enhance the Zn ion storage capability, La3+ with a big radius was selected to finely tune their nanostructure. The strategic introduction of La3+ to VO led to the formation of LaVO4 , which showed larger interplanar spacing, better electrical conductivity, and superior Zn-ion diffusion efficiency. These unique characteristics were beneficial in the (de)intercalation and the prevention of electrode degradation/collapse, thereby significantly strengthening the corresponding electrochemical performance. As a consequence, the cathode possessed a high specific capacity of 472.5â mAh g-1 at a current density of 0.38â A g-1 and displayed good rate performance, accompanied by enduring cycling stability (no decay after 2000â cycles). Besides, when equipped as an aqueous ZIB, it delivered an outstanding peak energy density of 341.9â Wh kg-1 and a peak power density of 3.22â kW kg-1 , surpassing most VO-based energy-storage devices.
RESUMEN
Rechargeable aqueous zinc-metal batteries (ZMBs) are considered as potential energy storage devices for stationary applications. Despite the significant developments in recent years, the performance of ZMBs is still limited due to the lack of advanced cathode materials delivering high capacity and long cycle life. In this work, we report a low-temperature and scalable synthesis method following a surfactant-assisted route for preparing manganese-doped hydrated vanadium oxide (MnHVO-30) and its application as the cathode material for ZMB. The as-prepared material possesses a porous architecture and expanded interlayer spacing. Therefore, the MnHVO-30 cathode offers fast and reversible insertion of Zn2+ ions during the charge/discharge process and delivers 341 mAh g-1 capacity at 0.1 A g-1. Moreover, the MnHVO-30||Zn cell retains 82% of its initial capacity over 1200 stability cycles, which is higher compared to that of the undoped system. Besides, a quasi-solid-state home-made pouch cell with an area of 3.3 × 1.6 cm2 and 3.6 mg cm-2 loading is assembled, achieving 115 mAh g-1 capacity over 100 stability cycles. Therefore, this work provides an easy and attractive way for preparing efficient cathode materials for aqueous ZMBs.
RESUMEN
Potassium ion batteries (KIBs), because of their low price, may exhibit advantages over lithium ion batteries as potential candidates for large-scale energy storage systems. However, owing to the large ionic radii of K-ions, it is challenging to find a suitable intercalation host for KIBs and thus the rechargeable KIB electrode materials are still largely unexplored. In this work, a reticular V2O5·0.6H2O xerogel was synthesized via a hydrothermal process as a cathode material for rechargeable KIBs. Compared with the orthorhombic crystalline V2O5, the hydrated vanadium pentoxide (V2O5·0.6H2O) exhibits the ability of accommodating larger alkali metal ions of K+ because of the enlarged layer space by hosting structural H2O molecules in the interlayer. By intercalation of H2O into the V2O5 layers, its potassium electrochemical activity is significantly improved. It exhibits an initial discharge capacity of â¼224.4 mA h g-1 and a discharge capacity of â¼103.5 mA h g-1 even after 500 discharge/charge cycles at a current density of 50 mA g-1, which is much higher than that of the V2O5 electrode without structural water. Meanwhile, X-ray diffraction and X-ray photoelectron spectroscopy combined with energy dispersive spectroscopy techniques are carried out to investigate the potassiation/depotassiation process of the V2O5·0.6H2O electrodes, which confirmed the potassium intercalation storage mechanisms of this hydrated material. The results demonstrate that the interlayer-spacing-enlarged V2O5·0.6H2O is a promising cathode candidate for KIBs.