Paper Title
Understanding Electrolyte Interactions With CUHCF Electrodes in Zinc-Ion Batteries

Abstract
This study explores the intricate interactions between copper hexacyanoferrate (CuHCF) electrodes and various aqueous electrolyte solutions in zinc-ion batteries, aiming to elucidate the effects of electrolyte concentration on the electrode’s electrochemical performance. CuHCF is recognized as a promising material for zinc-ion battery electrodes due to its unique structural properties and compatibility with aqueous systems. By employing a comprehensive set of analytical techniques, including cyclic voltammetry, charge-discharge measurements, and X-ray diffraction analysis, we systematically investigated how varying electrolyte concentrations influence the electrochemical behavior and structural integrity of CuHCF electrodes. Our findings reveal a significant dependence of the CuHCF electrode's charge-discharge capacity on electrolyte concentration. Specifically, an initial increase in capacity was observed as the electrolyte concentration increased from 1.0 to 2.0 mol dm‒3. However, further increases in concentration led to a decrease in capacity, which can be attributed to specific interfacial reactions occurring at low potentials (0–0.3 V) and concurrent structural changes in the CuHCF material. These interfacial reactions are closely linked to the hydration structure of zinc ions and the pH levels of the electrolyte, which together influence the stability and performance of the electrode. Moreover, our study highlights the critical role of optimizing electrolyte composition to achieve enhanced electrochemical performance in zinc-ion batteries utilizing CuHCF electrodes. The observed correlation between electrolyte concentration, zinc-ion hydration, and pH suggests that careful tuning of these parameters could lead to substantial improvements in battery efficiency and longevity. This work provides valuable insights into the fundamental interactions at the electrode-electrolyte interface, paving the way for the development of more efficient and durable aqueous zinc-ion batteries. Keywords - Zinc-Ion Battery, Aqueous Electrolyte, Energy Storage, Hydration, Electrolyte Concentration.