Rational Design of Zincophilic Ag/Permselective PEDOT:PSS Heterogeneous Interfaces for High-Rate Zinc Electrodeposition.

Abstract

Designing artificial interface is a promising strategy to protect Zn metal anode but achieving long Zn plating/stripping lifespans and efficient nucleation/deposition kinetics, particularly at high current densities, remains a challenge. In this study, a permselective zincophilic heterogeneous interface consisting of metallic Ag layer and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is designed via a simple chemical displacement and drop casting process. The artificial interface plays a multifunctional role in inhibiting dendrite growth/side reactions by reducing the nucleation barrier through a large number of Zn nucleation sites offered by the bottom Ag layer, homogenizing electrical field/Zn2+ flux and shielding SO4 2- migration via the compact, conducting, and Zn2+ -permselective PEDOT:PSS supporting layer. Moreover, the heterogeneous interface demonstrates enhanced structural integrity owing to the binder effect of PEDOT:PSS. As a result, the modified Zn anode demonstrates a cyclic lifespan of 200h and a reduced voltage hysteresis of ≈150mV at 20mA cm-2 /5 mAh cm-2 , far surpassing its counterparts. Moreover, the protected Zn anode allows the LiMn2 O4 -based full cells with remarkable rate and cycling performance. These findings provide new insight into the design of an efficient artificial interface for highly reversible and high-rate Zn electrodeposition.