ZIF-67-preloaded bacterial cellulose aerogel with strong Lewis acid–base interactions fabricating homogeneous solid composite electrolyte for lithium metal batteries

Abstract

Low ionic conductivity of solid electrolyte and unstable Li/solid electrolyte interface greatly restrict the development of solid-state lithium metal batteries (LMBs). In this study, a novel design strategy of solid composite electrolyte (SCE) was proposed by utilizing a ZIF-67-preloaded bacterial cellulose aerogel as a rigid scaffold. The as-prepared bacterial cellulose aerogel via freeze-drying route is highly porous with large quantities of accessible polar sites, which is beneficial to not only uniform growth of ZIF-67 nanoparticles on it owing to strong and adequate Lewis acid–base interaction between them, but also full accommodation of polymer matrix deriving from in situ polymerization of 1,3-dioxolane at the assistance of ZIF-67 “molecule bridge.” The well-distributed ZIF-67 with ordered channels further promotes Li+ migration and uniforms Li+ flux. These merits endow the SCE with continuous, rapid Li+ transport pathway as well as rigid-flexible coupled framework, thereby achieving highly reversible Li plating/stripping process and superior cycle capability of the LMBs.