Surface In Situ Compositing of Reactive Liquid‐Metal Anchored 2D Nanomaterial Skins for Active Composite Current Collectors

Abstract

ABSTRACT Surface functionalization through advanced skin‐like nanocoating is of great significance due to its tremendous potential in transforming materials technologies. Conventional strategies, including wet‐slurry coatings or vapor depositions, not only involve toxic solvents or expensive/time‐consuming processes, but also lead to weak interfaces. Here, we discover the compelled wetting effects of liquid‐metal (LM) during sponge‐rubbing coating, and propose a strategy of surface in situ compositing (SISC) that combines reactive liquid‐metal and van der Waals (vdW) materials (e.g., graphene and boron nitride) by sequenced sponge‐rubbing. Particularly, the components are in situ composited by the intensive frictional shearing of sponge‐rubbing, forming a robust metal‐conductive skin‐coating with ordered and mechanical interlocking microstructures anchored onto various substrates (e.g., polyimide, PI). For applications, the resultant vdM@PI film has been proven as a high‐performance active composite current collector (ACCC) capable of boosting the energy‐density and safety of batteries, an advanced Joule‐heating material for fast battery thermal‐management, and a photothermal material for efficient solar‐energy conversion.