Enhancement of Zn anode stability by diprophylline via construction of a water-lean electrical double layer and promotion of Zn(002) texture growth

Water-induced side reactions and unfavorable undesirable growth have restricted the further development of aqueous zinc-ion batteries. Electrolyte additives are considered as a pragmatic and viable approach to address this issue, owing to their ease of operation and satisfactory compatibility. This study identifies diprophylline as a promising additive for electrolytes, underscoring its favorable adsorption energy with zinc metal. The selective adsorption of diprophylline has been demonstrated to engender two primary effects. Firstly, it reconstructs a water-lean electric double layer, and secondly, it enhances the textured growth of Zn(002). Furthermore, diprophylline weakens the coordination bonding between Zn 2+ and H 2 O to regulate the solvation structure of Zn 2+ . Consequently, the zinc symmetric battery functions stably for over 2900 h at 5 mA cm −2 . The Zn||Cu asymmetric battery displays an average coulombic efficiency as high as 99.89 % across 4000 cycles. This research presents an affordable and easily operable electrolyte modification method for developing a Zn anode/electrolyte interface that exhibits excellent stability and reversibility.