Dual effect of organic/inorganic artificial protective layer to construct high-performance zinc metal anode

Abstract

Owing to their high specific capacity, low cost, environmental friendliness and safety, aqueous zinc ion batteries (AZIBs) have been one of the most popular battery systems. Nevertheless, dendrite growth, corrosion, hydrogen evolution and passivation on the anode side can seriously affect the lifetime of AZIBs. In view of this, this work constructs a protective layer compounded from inorganic (titanium silicate molecular sieve, TS) and organic (polyacrylonitrile, PAN) materials to realize the high-performance and dendrite-free zinc anode (Zn@PAN-TS). The cyano group in PAN has a coordination effect with zinc ions, which facilitates the transport of zinc ions. The porous TS can regulate the zinc ion flux through ion-confinement effect. Thus, the PAN-TS composite protective layer provides fast and orderly ion transport channels that modulate the uniform deposition of zinc through dual effect. Moreover, the experimental results show that the Zn@PAN-TS 50:1 anode has the best electrochemical performance. The corresponding MnO2 full cell maintained a high discharge capacity of 217.2 mAh·g−1 with a high retention rate of 81.1 % after 500 cycles at 0.3 A·g−1. This strategy offers fresh insight into constructing multifunctional hybrid interface for dendrite-free AZIBs.