“Three‐in‐One” Strategy that Ensures V₂O₅·nH₂O with Superior Zn²⁺ Storage by Simultaneous Protonated Polyaniline Intercalation and Encapsulation

Abstract

The structural engineering of vanadium oxides is considered as a research hotspot for enhancing their electrochemical performances applied to aqueous zinc‐ion batteries (AZIBs). In regard to the laggard Zn2+ transfer kinetic and fragile structure of V2O5·nH2O, herein, a feasible “three‐in‐one” strategy is adopted to design the structural engineering of V2O5·nH2O nanobelts through simultaneous protonated polyaniline intercalation and encapsulation (denoted as P‐VOH@P) to boost their Zn2+ storage. First, the enlarged interlayer pillared by polyaniline accelerates Zn2+ transfer speed and weakens electrostatic attraction between negative [VO] units and positive Zn2+. Second, polyaniline shell directly stabilizes the P‐VOH@P heterostructure. Third, the composition of protonated polyaniline not only improves the conductivity, but also contributes partial capacity though the reversible intrachain electronic migration. As expected, the Zn//P‐VOH@P cell exhibits specific capacities of 387 mAh g−1 with low‐mass‐loading cathode (2 mg cm−2) and 345 mAh g−1 with high‐mass‐loading cathode (5 mg cm−2) in coin cells and 360 mAh g−1 in pouch cells at 0.1 A g−1. Furthermore, the Zn//P‐VOH@P cell shows low capacity decay and good rate property. Herein, light is shed on a new strategy of engineering the vanadium oxide structure for postgeneration cathode material and paves a novel way to the advanced energy‐storage system.

Vanadium oxide - poly(3,4-ethylenedioxythiophene) cathodes for zinc-ion batteries: effect of synthesis temperature

“…300 mA•h•g −1 [11,12]. Nevertheless, the activation process for highly crystalline materials [13,14] restricts the development of commercial vanadiumbased AZIBs. The activation process hinders the initial performance of the cells and results in their low cycling stability due to vanadium dissolution during both charging/discharging and storage [11,15].…”

Synthesis of Zn2+-Pre-Intercalated V2O5·nH2O/rGO Composite with Boosted Electrochemical Properties for Aqueous Zn-Ion Batteries

“…After that, some objects (e.g., various metal ions, different polymers) are introduced to tune the lamellar structure of VOH. After adjusting the interlayer spacing, electrochemical properties of intercalated VOH were significantly boosted [ 29 , 30 , 31 , 32 , 33 , 34 ]. For instance, Liu et al reported that polyaniline-intercalated VOH shows an expanded interlayer space of ~14 Å delivering a capacity of 354 mAh·g −1 at 0.1 A·g −1 and good cycle stability [ 35 ].…”

Vanadium Oxide-Poly(3,4-ethylenedioxythiophene) Nanocomposite as High-Performance Cathode for Aqueous Zn-Ion Batteries: The Structural and Electrochemical Characterization

“…Nevertheless, one of the major problems affecting the performance of vanadium oxide-based cathode materials is their dissolution [ 11 , 18 ], which leads to unsatisfactory performance, especially at lower current densities. In addition, highly crystalline vanadium oxide-based materials require activation of the material [ 20 , 21 ], which hinders the performance in the initial cycles.…”

“…Several strategies exist to overcome these drawbacks. These include nanostructuring [ 22 ], addition of conducting polymers [ 20 , 23 ] or carbons [ 24 , 25 ] as components or coatings, and inclusion of different metal ions into the crystal structure of the material via pre-intercalation [ 25 , 26 ] or manufacturing of pillared structures, i.e., the solids with the interlayer distance permanently expanded by inserting a strongly bound guest ion or molecule [ 9 , 27 , 28 , 29 ].…”