Uniform wide-channel gel polymer electrolyte with consistent head-to-tail supramolecular arrangement for enhanced aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) are emerging as a promising energy storage solution due to their safety, costeffectiveness, and high energy density. However, challenges such as dendrite growth, electrolyte stability, and ionic conductivity present significant hurdles. In this work, we developed a carboxylated cyclodextrin (CCD)based gel polymer electrolyte (CCD-GPE) with highly ordered head-to-tail aligned CCD units, achieved through self-assembly with polyethylene oxide (PEO). This CCD-GPE exhibits a uniform channel structure that enables efficient Zn2* flux distribution and effectively suppresses zinc dendrite growth. The extended carboxyl groups in the CCD-GPE regulate the Zn2* solvation structure, contributing to a stable electrolyte-electrode interface. This innovation achieves impressive electrochemical performance, including an ion conductivity of 18.5 mS cm- 1, a superior ion transference number (0.64), and 95 % capacity retention over 1000 cycles at 2.0 A g- 1 in Zn||MnO2 cells. Moreover, CCD-GPE not only reduces side reactions such as hydrogen evolution but also prolongs Zn anode's lifespan by promoting uniform Zn2* migration. These advancements position CCD-GPE as a strong candidate for practical applications in aqueous Zn-ion batteries, paving the way for enhanced energy storage solutions.