Uniform Zinc Deposition Regulated by a Nitrogen-Doped MXene Artificial Solid Electrolyte Interlayer.

Abstract

The dendrite growth and side reactions of zinc metal anode in mildly acidic electrolytes seriously hinder the practical application of aqueous zinc-ion battery. To address these issues, an artificial protective layer of nitrogen-doped MXene (NMX) is used to protect the zinc anode. The NMX protective layer has high conductivity and uniformly distributed zincophilic sites, which can not only homogenize the local electric field on the electrode interface but also accelerate the kinetics for Zn deposition. As a result, the NMX protective layer induces uniform zinc deposition and reduces the overpotential of the electrode. Encouragingly, this NMX-protected Zn anode can cycle stably for 1900h at 1mA cm-2 and 1 mAh cm-2 . In asymmetric cells, it achieves high cycle reversibility with an average Coulomb efficiency of 99.79% for 4800 cycles at 5mA cm-2 .