In Situ Induced Coordination between a “Desiccant” Interphase and Oxygen‐Deficient Navajoite towards Highly Efficient Zinc Ion Storage

Abstract

Poor interfacial stability, undesired side reactions, and sluggish reaction kinetics greatly impair the zinc storage performance of vanadium‐based cathode materials. Here, an in situ electrochemical conversion strategy is employed to synergistically deal with these issues. Through the initial electrochemically charging, the CaV4O9 cathode is reconstructed into an oxygen‐deficient navajoite V5O12−x·6H2O (HVOd) coated by gypsum (CaSO4·2H2O (GP)) layers, denoted as GP‐HVOd. The GP interphase with “desiccant” properties can not only suppress the vanadium dissolution, but also regulate the desolvation of hydrated Zn2+ through its strong hydrophilicity and space confinement, thus facilitating the interfacial kinetics with reduced activation energy. With less water molecules eroding the HVOd bulk phase, the typical water‐induced by‐products can also be eliminated. Moreover, highly reversible Zn2+ storage is guaranteed by HVOd with in situ generated oxygen defects. Under such coordination, GP‐HVOd delivers a high capacity of 402.5 mA h g−1, excellent cycling stability at 0.2 A g−1 with 99.7% capacity retention after 200 cycles, mighty rate performance, and high tolerance to sub‐zero environments (143.2 mA h g−1 retained at 3 A g−1 and −25 °C). This work provides a new opportunity to propel the development of highly efficient zinc‐storage cathodes.

A cerium vanadate/S heterostructure for a long-life zinc-ion battery: efficient electron transfer by the anchored sulfur

“…1j, a strong signal is detected at around 3443 G for CeVS, which corresponds to the effective gyromagnetic ratio at an isotropic g of 1.96 and provides evidence for the oxygen vacancies. 27,28…”

“…1j, a strong signal is detected at around 3443 G for CeVS, which corresponds to the effective gyromagnetic ratio at an isotropic g of 1.96 and provides evidence for the oxygen vacancies. 27,28 In order to further determine the compositions in CeVO and CeVS, thermogravimetric (TG) curves were recorded from room temperature to 800 °C under a N 2 atmosphere. For comparison, the TG curves of V 2 O 5 and VS 2 were recorded under the same conditions.…”

Structural Engineering of Vanadium Oxide Cathodes by Mn2+ Preintercalation for High-Performance Aqueous Zinc-Ion Batteries

“…39,40 Meanwhile, the proportion of the O d peak in the MnVO nanoribbons increased significantly, which may be attributed to the introduction of positive Mn 2+ ions during the reduction process, thus making it more favorable for the formation of oxygen vacancies in order to balance the charge. 24,28,41,42 Figure 2f shows the Mn 2p XPS spectrum of the MnVO nanoribbons, demonstrating the double peaks of Mn 2p 3/2 and Mn 2p 1/2 and the accompanying satellite peaks. 43,44 Therefore, the XPS spectra of O 1s and Mn 2p further confirm that Mn 2+ intercalation leads to the increase of oxygen vacancies in the lattice, 45 which is beneficial to the electrochemical performance of the MnVO electrode.…”

How About Vanadium‐Based Compounds as Cathode Materials for Aqueous Zinc Ion Batteries?

“…The discharge capacity of V 5 O 12 6H 2 O is 354.8 mAh g −1 (0.5 A g −1 ), the initial CE is up to 99.5%, the energy density is up to 194 Wh kg −1 (2100 W kg −1 ), and the capacity retention rate is up to 94% after 1000 cycles. Huang and coworkers [ 204 ] made CaV 4 O 9 cathode reconstruct as the oxygen‐deficient V 5 O 12‐x 6H 2 O coated by gypsum layers (GP‐HVO d ) through the initial electrochemically charging (Figure 10b ). The crystal structure of V 5 O 12‐x 6H 2 O (HVO d ) is shown in.…”

“…Figure 10c . Based on its structure, Huang and colleagues [ 204 ] used DFT calculations to reveal the role of O d in optimizing electronic properties. The overall Zn 2+ storage mechanism of GP‐HVO d was shown in Figure 10d .…”