Hierarchical Metal Oxide Topographies Replicated from Highly Textured Graphene Oxide by Intercalation Templating.

Confined assembly in the intersheet gallery spaces of two-dimensional (2D) materials is an emerging templating route for creation of ultrathin material architectures. Here, we demonstrate a general synthetic route for transcribing complex wrinkled and crumpled topographies in graphene oxide (GO) films into textured metal oxides. Intercalation of hydrated metal ions into textured GO multilayer films followed by dehydration, thermal decomposition, and air oxidation produces Zn, Al, Mn, and Cu oxide films with high-fidelity replication of the original GO textures, including "multi-generational", multiscale textures that have been recently achieved through extreme graphene compression. The textured metal oxides are shown to consist of nanosheet-like aggregates of interconnected particles, whose mobility, attachment, and sintering are guided by the 2D template. This intercalation templating approach has broad applicability for the creation of complex, textured films and provides a bridging technology that can transcribe the wide variety of textures already realized in graphene into insulating and semiconducting materials. These textured metal oxide films exhibit enhanced electrochemical and photocatalytic performance over planar films and show potential as high-activity electrodes for energy storage, catalysis, and biosensing.