Supramolecule-Based Excluded-Volume Electrolytes and Conjugated Sulfonamide Cathodes for High-Voltage and Long-Cycling Aqueous Zinc-Ion Batteries

Abstract

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

Trifunctional Rb+-Intercalation Enhancing the Electrochemical Cyclability of Ammonium Vanadate Cathode for Aqueous Zinc Ion Batteries

“…Subsequently, the content of Rb + in the separator tends to come to equilibrium after the second cycle, indicating the steady chemical environment of Rb + reached in the AZIB system. 39 Being inspired by electrolyte additive engineering, 33,34 the Zn(CF 3 SO 3 ) 2 -Rb electrolyte was first designed to investigate the effect of deintercalated Rb + cations on the hydrogen evolution reaction (HER) of Zn(CF 3 SO 3 ) 2 aqueous electrolyte and the dendrite growth of the zinc anode, as well as the kinetic and cycling performance. In this control experiment, the Zn(CF 3 SO 3 ) 2 -Rb electrolyte was prepared with 10 mg of Rb + per 10 mL of the electrolyte referring to ICP results in Figure S6.…”

NH4+ Charge Carrier Coordinated H‐Bonded Organic Small Molecule for Fast and Superstable Rechargeable Zinc Batteries

“…To rationalize the significant metrics differences between NH 4 OTF and Zn(OTF) 2 aqueous environments, we first studied the solvation behaviors and coordination process of two charge carriers in DNPT. Generally, the solvation behaviors affect the electrochemical properties, entailing the ion‐migration kinetics in bulk electrolytes and thermodynamic desolvation process at cathode/electrolyte interfaces [13a,24] . Molecular dynamics simulations were performed to depict the solvation structures of non‐metallic NH 4 + and metallic Zn 2+ ions in aqueous solvent.…”

Advances in organic cathode materials for aqueous multivalent metal-ion storage

“…p-Type organic materials (e.g., triphenylamine derivatives, organosulfur polymers) lose electrons from the chain and the remaining positive charges react with electrolyte anions to balance the charge state upon charging. 29,60,61,71 p-Type organic materials, which rely on anion redox chemistry and undergo almost no bond rearrangement, have a considerable opportunity for use in high-power density energy storage. For instance, the solid-state electrooxidation approach was demonstrated for the fabrication of novel p-type cathodes (Fig.…”

“…Besides, the electrochemistry of organic cathode materials is not confined to the desired metal carriers (Al 3+ , Ca 2+ , Mg 2+ , Zn 2+ ), and non-metal ions (e.g., H + , OTF À , SO 4 2À , [ZnCl 4 ] 2À , NH 4 + ) have been frequently investigated as charge carriers in multivalent metal-ion storage systems. 18,33,71,[96][97][98][99][100][101] Protons (H + ) are considered as attractive charge carriers due to their merits of small radius and light atomic mass. 102,103 The Grotthuss mechanism, a special proton hopping process that takes place in aqueous environments, gives protons unparalleled ion mobility to consequently realize the fast H + (de)sorption kinetics.…”