INVESTIGATION OF ZINC HEXACYANOFERRATE FOR AQUEOUS ZINC ION BATTERIES

Dovilė Škarnulytė1, Jurgis Pilipavičius1, 2, Linas Vilčiauskas1, 2

1 Centre for Physical Sciences and Technology, Sauletekio av. 3, LT-10257, Vilnius, Lithuania

2 Institute of Chemistry, Vilnius University, Naugarduko 24, LT-03225, Vilnius, Lithuania

[email protected]

The Prussian blue analogue zinc hexacyanoferrate (Zn\(_3\)[Fe(CN)\(_6\)]\(_2\)), which is the focus of this research, has an open-channel framework. The unique structure makes this material suitable for the storage of ions and even small molecules [1]. Moreover, due to the abundance of zinc and iron in the world, and the simplicity of the co-precipitation synthesis method, used to obtain this compound, ZnHCF has become one of the potential candidates for being utilized for the use as cathode in aqueous zinc-ion batteries [2]. Aqueous electrolytes, despite having a narrower electrochemical stability window, provide a safer environment compared to the commonly used organic electrolytes [3]. In addition, the reduction potential of Zn (-0.76 V vs. standard hydrogen electrode, SHE) makes it a significantly safer choice for ambient conditions than alkaline or alkali earth metal compounds [4].​

In this work, we have used structural characterisation methods to analyse the dependence of the final phase obtained to changes in the synthesis procedure. In addition, the electrochemical performance of the samples was investigated as well as the relationship between said performance and structural characteristics of the material.


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[2] Zhang, L., Chen, L., Zhou, X. & Liu, Z. Towards High-Voltage Aqueous Metal-Ion Batteries Beyond 1.5 V: The Zinc/Zinc Hexacyanoferrate System. Adv Energy Mater 5, (2015).

[3] Kundu, D., Adams, B. D., Duffort, V., Vajargah, S. H. & Nazar, L. F. A high-capacity and long-life aqueous rechargeable zinc battery using a metal oxide intercalation cathode. Nat Energy 1, 1–8 (2016).

[4] Wang, Q., Li, J., Jin, H., Xin, S. & Gao, H. Prussian‐blue materials: Revealing new opportunities for rechargeable batteries. InfoMat 4, e12311 (2022).