Van der Waals Interaction-Driven Self-Assembly of V₂O₅Nanoplates and MXene for High-Performing Zinc-Ion Batteries by Suppressing Vanadium Dissolution

Abstract

Aqueous zinc-ion batteries (AZIBs) are attractive energy storage devices that benefit from improved safety and negligible environmental impact. The V2O5-based cathodes are highly promising, but the dissolution of vanadium is one of the major challenges in realizing their stable performance in AZIBs. Herein, we design a Ti3C2T x MXene layer on the surface of V2O5 nanoplates (VPMX) through a van der Waals self-assembly approach for suppressing vanadium dissolution during an electrochemical process for greatly boosting the zinc-ion storage performance. Unlike conventional V2O5/C composites, we demonstrate that the VPMX hybrids offer three distinguishable features for achieving high-performance AZIBs: (i) the MXene layer on cathode surface maintains structural integrity and suppresses V dissolution; (ii) the heterointerface between V2O5 and MXene enables improved host electrochemical kinetics; (iii) reduced electrostatic repulsion exists among host layers owing to the lubricating water molecules in the VPMX cathode, facilitating interfacial Zn2+ diffusion. As a result, the as-made VPMX cathode shows a long-term cycling stability over 5000 cycles, surpassing other reported V2O5-based materials. Especially, we find that the heterointerface between V2O5 and MXene and lubricated water molecules in the host can achieve an enhanced rate capability (243.6 mAh g–1 at 5.0 A g–1) for AZIBs.

Vertically Aligned Bismuthene Nanosheets on MXene for High-Performance Capacitive Deionization

“…The electron accumulation at the heterointerface is beneficial to facilitate electron transport. 49 Moreover, the chloride diffusion energy barrier of the Bi-ene NSs@MXene heterostructure and bulk bismuth was evaluated through the climbing-image nudged elastic band (CI-NEB) method. 50 As shown in Figure 6c, the diffusion paths on the surface of bulk bismuth and the Bi-ene NSs@MXene heterostructure are similar from hole site to top site then to hole site.…”

“…Furthermore, Figure b shows the differential charge density of the Bi-ene NSs@MXene heterostructure with charge accumulation near the surface of MXene and charge depletion near Bi-ene. The electron accumulation at the heterointerface is beneficial to facilitate electron transport . Moreover, the chloride diffusion energy barrier of the Bi-ene NSs@MXene heterostructure and bulk bismuth was evaluated through the climbing-image nudged elastic band (CI-NEB) method .…”

Chrysanthemum-like Polyaniline-Anchored PANI0.22·V2O5·0.88H2O-Hybridized Cathode for High-Stable Aqueous Zinc-Ion Batteries

“…This result indicates that the P-60-120 °C electrode enables fast charge migration kinetics, thus leading to a superior rate capability. 22,26,43…”

“…47−49 Furthermore, the dissolution of active materials in the electrode is considered a key factor in battery capacity degeneration. 7,22 As depicted in Figure S10 prolongation of soaking time, the pure-V 2 O 5 electrode undergoes the most serious dissolution issues (11.66 mg L −1 after 7 days). Followed by the P-60-140 °C electrode (1.82 mg L −1 ), which is attributed to the low-valence vanadium species that will weaken the V−O bond strength of the V 2 O 5 framework to a gradual loss of the active materials.…”

“…To tackle these problems, a series of guest ions/molecules preintercalated in V-based oxide materials are proposed to stabilize their crystal frameworks and enlarge the interlayer spacing for facile Zn 2+ diffusion. However, most hetero ions are redox inactive and are liable to be extracted irreversibly during the repeat discharge processes, which will be at the expense of the overall reversible capacity of the materials. − Recent investigations demonstrate that introducing conductive organic small molecules [poly­(3,4-ethylene dioxythiophene), polyaniline, etc. ] to the interlayer of layered oxides allows for interlayer regulation and stabilizing structures via forming hydrogen bonds between the −NH 2 group and the V–O layer. − However, most of the so-called preinserted hydrated V 2 O 5 materials exhibit 2D belt-like or sheet-like architectures with relatively low specific surface areas.…”