Stable artificial solid electrolyte interphase films for lithium metal anode via metal–organic frameworks cemented by polyvinyl alcohol

Abstract

Lithium (Li) metal anodes have shown a huge potential for next-generation energy storage because of the high theoretical specific capacity and negative potential. Nevertheless, due to the change in the volume and the existence of Li dendrites, the application of the Li metal anode is significantly limited. For the purpose of developing a stable Li metal anode to avoid Li dendrite formation, we introduced a stable artificial solid electrolyte interphase (SEI) film, which was prepared by polyvinyl alcohol (PVA) cementing a metal organic framework (Zn-MOF). The environment-friendly and non-toxic PVA acted as a “glue” to cement the rigid Zn-MOF. The artificial SEI film had high Li ion conductivity and excellent flexibility, which is beneficial for uniform lithium flux, inhibiting dendrite growth and easing the volume change. Consequently, benefitting from the safeguard of the Zn-MOF/PVA artificial SEI film, the anode delivered high coulombic efficiency above 97.7% beyond 250 cycles at a current density of 3 mA cm⁻².