Supramolecule-Based\nExcluded-Volume Electrolytes and\nConjugated Sulfonamide Cathodes for High-Voltage and Long-Cycling\nAqueous Zinc-Ion Batteries

Aqueous zinc-ion batteries (AZIBs) have attracted great\nattention\nfor sustainable energy storage due to their high safety and low cost.\nHowever, the performance of the AZIBs is restricted by electrolyte\ndecomposition, cathode degradation, and anodic dendrite growth. Herein,\nwe propose (2-hydroxypropyl)-β-cyclodextrin electrolytes with\nsynergistic functions of an excluded-volume effect and hydrogen-bond\nnetworks, which greatly reduce the activity of water molecules, expand\nthe electrochemical window of the electrolyte, inhibit the dissolution\nof active materials, and suppress the growth of zinc dendrites. Moreover,\norganic conjugated sulfonamides are demonstrated to be promising cathodic\nmaterials with stable structures and high-potential redox sites. The\nas-constructed AZIBs exhibit a high open-circuit voltage (1.7 V),\na wide operating temperature range (−20 to +90 °C), and\nlong cycling life (with a capacity retention of 98.3% after 2000 cycles\nat 10 C). The rational design of an organic electrode and an advanced\nelectrolyte is a promising route to boost the overall performances\nof aqueous secondary batteries.