Reducing the Surface Tension of Zn Anodes by an Abietic Acid Layer for High Redox Kinetics and Reversibility

Aqueous zinc batteries are appealing devices for cost-effective and environmentally sustainable energy storage. However, the critical issues of uncontrolled dendrite propagation and side reactions with Zn anodes have hindered their practical applications. Inspired by the functions of the rosin flux in soldering, an abietic acid (ABA) layer is fabricated on the surface of Zn anodes (ABA@Zn). The ABA layer protects the Zn anode from corrosion and the concomitant hydrogen evolution reaction. It also facilitates fast interfacial charge transfer and horizontal growth of the deposited Zn by reducing the surface tension of the Zn anode. Consequently, promoted redox kinetics and reversibility are simultaneously achieved by the ABA@Zn. It demonstrates stable Zn plating/stripping cycling over 5100 h and a high critical current of 8.0 mA cm –2 . Moreover, the assembled ABA@Zn|(NH 4 ) 2 V 6 O 16 full cell delivers outstanding long-term cycling stability with an 89% capacity retention after 3000 cycles. This work provides a straightforward yet effective solution to the key issues of aqueous zinc batteries.