Zincophilic host with lattice plane matching enables stable zinc anodes in aqueous zinc-ion batteries.

Abstract

The practical application of aqueous zinc-ion batteries (AZBs) as attractive energy storage devices is severely hampered by the uncontrollable zinc dendrite growth on the metal anode. Here, a lightweight and flexible free-standing membrane of MXene/Ag nanowires (AgNWs) was synthesized via vacuum filtration to support the zinc anode. The 3D cross-linked network structure provides ample space for densely packed zinc electrodeposition. Zincophilic AgNWs that exhibit a low lattice plane mismatch with zinc lower the nucleation barrier for zinc, inducing uniform nucleation and lateral growth of zinc on the substrate. In addition, the 3D network framework effectively reduces the local current density and area capacity of the anode, creating a uniform electric field that is not conducive to zinc dendrite formation. Consequently, the highly reversible Zn@MXene/AgNWs composite anode exhibits long cycle stability of 1000 h at 2.0 mA cm^-2, 1.0 mAh cm^-2 in the symmetrical battery. The full battery assembled with a sodium vanadate (NVO) cathode demonstrates excellent rate performance and long cycle life (2000 cycles at 5.0 A/g). The design of zincophilic hosts with high lattice plane matching provides a promising strategy for realizing dendrite-free zinc anodes for AZBs.