Triple Redox-Enabled High-Entropy Metal-Organic Coordination Driving High-Performance Aqueous Zinc-Ion Batteries

High entropy (HE) nanomaterials offer a promising strategy for advancing aqueous zinc-ion batteries (AZIBs). In this study, 1,4-dihydroxyanthraquinone (1,4-DHAQ) is employed as an organic ligand to coordinate with multiple metal ions, forming a series of binary to quinary high-entropy (HE) nanomaterials. All synthesized materials exhibit a layered flower cluster structure. Among them, MnCoNiFeCu-1,4-DHAQ (denoted as HE-1,4-DHAQ) demonstrates the largest specific surface area and pore volume, along with superior electronic conductivity. HE-1,4-DHAQ delivers outstanding electrochemical performance, maintaining a high specific capacity of 222.6 mAh·g^-1 after 150 cycles at a current density of 0.3 A·g^-1. A combination of in situ powder X-ray diffraction, ultraviolet and visible spectrophotometry, and Fourier transform infrared, together with ex situ X-ray photoelectron spectroscopy and elemental mapping, is employed to comprehensively elucidate the structural evolution and reaction mechanisms during cycling. The results reveal that HE-1,4-DHAQ exhibits excellent structural stability and a highly reversible Zn²⁺ insertion/extraction mechanism. Moreover, the involvement of three active centers, namely the ─OH groups on the ligand, Mn, and Cu, is confirmed. Notably, HE-1,4-DHAQ has been applied as a cathode in soft-pack batteries, gel electrolyte, and screen-printed devices, demonstrating strong potential for energy storage and flexible electronics.