Surface Engineering with Interfacial Poly(glutamic acid)/MXene/Aramid Nanofibers Protective Layer for Dendrite-Free Zinc Anodes

Abstract

Aqueous zinc-ion batteries (AZIBs) use zinc metal as anodes are expected to be used for large-scale energy storage due to their good safety, low cost, environmental friendliness, etc. However, the zinc dendrite growth and associated side reactions seriously cause low Coulomb efficiency and reduce the cycle life of AZIBs, finally hampering further practical application. Herein, the γ-poly(glutamic acid) (γ-PGA)/aramid nanofibers (ANFs)/ MXene (PAM) protection layer was designed toward a dendrite-free Zn metal anode. The PAM layer with a three-dimensional (3D) network formed by strong hydrogen bonding interactions effectively inhibits the growth of zinc dendrites, corrosion of the electrolyte, and hydrogen precipitation due to the reduced nucleation overpotential, which facilitates uniform galvanization/de-zincification. At a current density of 0.1 mA•cm −2 and 0.1 mAh•cm −2 , the cycle life of PAM@Zn//PAM@Zn symmetric cell could extend to 3500 h. Meanwhile, the PAM@Zn//V 2 O 5 full cell could also exhibit a capacity retention of 82.49% after 1500 cycles at 1 C. This strategy of designing a polymer-based composite protection layer by integrating the advantages of different materials opens up more possibilities for the development of a dendrite-free Zn anode.