Unveiling the X‐Ray Absorption Chemistry of H_3.78V₆O₁₃ Cathode for Aqueous Zinc‐Ion Batteries

Abstract

The low cost and intrinsic safety of rechargeable aqueous zinc‐ion batteries (ZIBs) contribute to their significant potential in grid‐level energy storage systems. However, the limited cathode options still hinder the development of ZIBs, which always delivers poor rate capacities and cycling stability. Herein, Monoclinic phase H3.78V6O13 microspheres with a stable internal framework and intrinsic metallic properties as a high‐performance cathode for ZIBs are proposed and utilized. The reversible Zn2+insertion/de‐insertion mechanism in H3.78V6O13through ex situ X‐ray diffraction, X‐ray absorption near‐edge structure, and in situ Raman involves the enlargement/shrink of interplanar distance, the decrease/increase of the V valance, and the open/recombine of V─O/V─V bonds. Further, experiments and theoretical calculations elucidate the superior electrochemical performance and extraordinary reaction kinetics in H3.78V6O13. The as‐prepared H3.78V6O13 cathode delivers high specific capacity of 406 mAh g–1 at 0.1 A g–1, excellent structure stability with 100% manifested after 120 cycles at 0.5 A g–1, 72.9% retained after 15 000 cycles at 10 A g–1. This research offers distinctive perspectives on the development of high‐performance cathode materials for ZIBs and enhances the understanding of the electrochemical reaction mechanisms of vanadium oxides.

A long-term stable zinc metal anode enabled by a mannitol additive

“…3a, the Fourier transform infrared spectroscopy (FTIR) spectrum of the ZnSO 4 electrolyte has prominent absorption peaks at 3135 cm −1 and 1085 cm −1 , corresponding to the vibrations of O–H and SO 4 . 2–15 These two adsorption peaks are weaker, and the position also shows significant movement, indicating that the electrostatic-constrained environment of Zn 2+ ions has been regulated after introducing the mannitol additive. Furthermore, the solvation behavior was analyzed by Raman spectroscopy as shown in Fig.…”

“…5,6 Recently, aqueous rechargeable zinc ion batteries (ZIBs) hold significant promise as viable alternatives to LIBs, owing to the outstanding physicochemical characteristics of Zn metal, such as cost-effectiveness, environmental sustainability, high capacities (5855 mA h cm −3 ), and inherent safety when used with aqueous electrolytes. 7–10 Despite advancements, the practical use of ZIBs is impeded by low coulombic efficiency (CE) and the formation of significant zinc dendrites. These obstacles stem from two main aspects: firstly, the thermodynamic instability caused by the lower redox potential of Zn metal compared to H 2 O/H 2 in aqueous solutions leads to the hydrogen evolution reaction (HER) and suboptimal coulombic efficiency (CE).…”

Unlocking Double Redox Reaction of Metal–Organic Framework for Aqueous Zinc‐Ion Battery

“…The cathode materials play a critical role for improving their electrochemical performance. Up to now, various cathodes of AZIBs have been reported, such as manganese‐based materials, [6] vanadium‐based materials, [7] organic materials, [8] Prussian blue analogues, [9] and so on. Though some progresses have been made to enhance their electrochemical performance, these cathodes still face many challenges.…”

Multifunctionalized Supramolecular Cyclodextrin Additives Boosting the Durability of Aqueous Zinc-Ion Batteries

“…Over the past few decades, lithium-ion batteries have achieved great success in various consumer electronics, portable devices, and electric vehicles. − However, with the increasing costs, the safety issue arising from the flammability of organic electrolytes, and the demand of high energy density, it is urgent to explore the next-generation energy storage technologies. , As one of the most promising candidates for large-scale energy storage, aqueous zinc-ion batteries have sparked great interest among researchers due to their low cost, intrinsic safety, environmental friendliness, and high theoretical capacity of zinc metal. − However, in order to achieve the commercial applications of aqueous zinc-ion batteries, there are still many technical obstacles to be overcome, such as the low coulombic efficiency (CE), severe dendrite growth, hydrogen evolution, formation of byproducts on the Zn anode surface, and so on . Therefore, many strategies have been proposed to address the above issues of the Zn anode, including electrolyte composition optimization, , interface modification, structure design, and so on.…”