Stabilizing Zn Anodes by Molecular Interface Engineering with Amphiphilic Triblock Copolymer

Abstract

Aqueous Zn-based electrochemical technologies hold promise for large-scale energy storage applications, yet challenges persist in the unsatisfied Zn reversibility arising from an unstable Zn/electrolyte interface. Here, we employ molecular interface engineering using amphiphilic Pluronic triblock copolymers as electrolyte additives to stabilize the Zn anodes. With a balanced hydrophilic−hydrophobic nature, Pluronic F127 adsorbed on the Zn surface constructs a hydrodynamic interphase, where the hydrophobic PPO center shields the Zn surface from water-induced side reactions, while PEO side blocks guide the homogeneous Zn 2+ redistribution. Additionally, F127 contributes to the Zn 2+ solvation structure to weaken the water activity at the interfacial region. As a result, F127 additive enables cycling durability over 9300 and 3100 h at 1 and 5 mA cm −2 , respectively, and considerable cyclability with highcapacity retention across a wide current density range in Zn||VO 2 full cells. This study highlights the potential of amphiphilic block copolymers in stabilizing metallic anode interfaces in aqueous electrolytes.

Structural and Interfacial Engineering Strategies for Constructing Dendrite-Free Zinc Metal Anodes

“…Furthermore, the compatibility between the modified Zn anode and various cathode systems should be further evaluated due to the distinct working mechanisms of different cathodes. For instance, in Zn–iodine batteries, coating protective layers on the ZMA may be more beneficial due to the severe shuttle effect of intermediate polyiodides and the potential corrosion of the anode by polyiodides. − Moreover, the depth of discharge deserves increased attention due to the extensive utilization of Zn metal in various battery types. − A thorough understanding of the discharge depth and its impact on the performance and longevity of ZMAs should be explored. Considering these above concerns, the feasible design of Zn-based full batteries at a pouch-cell level is an ultimate challenge that restrict the practical utilizations of ZMAs.…”

Gradient Lithium Ion Regulation Current Collectors for High-Performance and Dendrite-Free Li Metal Batteries

“…Artificial surface electrolyte interface (SEI) film is one of the effective strategies that has been devoted to solving the problem of lithium dendrites. − The optimal lithiophilic sites and promoted Li + transport pathways are crucial for excellent electrochemical performance. The SEI film containing lithium halide, lithium nitride, lithium fluoride, or lithium phosphide is generated in situ by adding a halogen-rich, N-rich, or P-rich solution dropwise to the lithium metal anode surface, respectively.…”