Controlled deposition via a bifunctional layer enables dendrite-free zinc metal batteries

Suppressing the Zn dendrites of the anode is regarded beneficial to constructing the high safe and long life Zn metal battery. However, it is still an austere challenge to realizing the even zinc nucleation and controllable growth. Herein, we reported a dendrite-free Zn anode based on the protection of Ag nanoparticles modified reduced graphene oxide (rGO/Ag@Zn). Among them, the parallelly aligned rGO layers drive the epitaxial deposition of Zn along (0 0 2) plane, while ultrafine Ag nanoparticles serve as the zincophilic seeds anchored on rGO to modulate uniform Zn-ion distribution and realize horizontally confined Zn deposition. Such synergistic effect restrains the growth of Zn dendrites, enabling an ultra-stable Zn anode. Therefore, the rGO/Ag@Zn symmetric cell can steadily cycle over 2200 h with a lower voltage polarization of 33.1 mV at a high current density and areal capacity (10 mA cm−2 and 5 mA cm−2). Meanwhile, the full cell matched with V2O5 cathode delivers a high capacity of 157.5 mA h g−1 after 4000 cycles at 5 A/g. This bifunctional protection layer on Zn anode leads a dendrite-free Zn platting/stripping and provides a facile approach for high-performance zinc ion batteries.