Tetrahydrofuran-mediated hydrogen bonding for stabilized zinc anodes

Abstract

Aqueous zinc-ion batteries (AZIBs) have emerged as a promising candidate for large-scale energy storage. However, the hydrogen evolution reaction (HER) is a key factor affecting the stability of zinc anodes. Here, a tetrahydrofuran (THF)-mediated hydrogen bonding strategy is adopted to develop a THF-based electrolyte (ZS-T electrolyte), in which strong hydrogen bonds between THF and H₂O molecules block the transmission of protons in water to inhibit the HER, thereby improving the stability of zinc anodes. Therefore, the corrosion rate of zinc anode decreases to 3.40 × 10⁻⁵ A cm⁻² in the optimized ZS-T-5 electrolyte, and the zinc nucleation overpotential drops to 28.97 mV. The Zn//Zn symmetric battery cycled for over 1000 hours at 1 mA cm⁻²; the Zn//Cu half-cell cycled 1000 times with an average coulombic efficiency of 99.32%; and the Zn//MnO₂ full cell cycled 800 times at 1 A g⁻¹, with the capacity retention rate increasing from 34.1% to 63.3%.