Nitrogen-doped graphene enables stable zinc anode for long-term cycling aqueous Zn-ion batteries

Aqueous zinc ion batteries (ZIBs) with high theoretical capacity and good safety have emerged as one of the most promising sustainable energy storage systems. However, the irreversible dendritic growth on the surface of Zn anodes results in efficiency sharply decreasing, which seriously hinders the development of ZIBs. Herein, a nitrogen-doped graphene protective layer was introduced to Zn anode (N-rGO@Zn) using a simple self-assembly method, which reduced the contact resistance between the electrolyte and the electrode interface, improved the diffusion kinetics of Zn2+ and the occurrence of side reactions. Implementing this stable interface enhanced cycling at the current density of 1 mA/cm2 of 1 mAh/cm2 with reversibility of Zn plating/stripping for more than 1200 h. Furthermore, when the N-rGO@Zn anode is assembled with MnVO cathode, MnVO//N-rGO@Zn ZIB achieves a high specific capacity of 151.0 mAh/g at 10 A/g and maintains 97.0% after 2500 cycles. This N-rGO@Zn provides theoretical guidance for inhibiting dendrite growth and improving the stability of Zn anode.