Graphene oxide-mediated formation of freestanding, thickness controllable metal oxide films

Abstract

Graphene-based sheets which possess a unique nanostructure and properties have been appealing as promising nanoscale building blocks of film materials. Herein, graphene-based sheets have been not only used as support templates to fabricate graphene-particle composite films, but also as effective sacrificial templates to prepare freestanding particle films. Freestanding metal oxide particle (Fe₂O₃ and TiO₂) films are obtained by synthesis of graphene oxide-particle precursor composites, assembling these composite sheets into freestanding films by vacuum filtration and the subsequent calcination in air. Moreover, the thickness and certain properties of these as-prepared particle films can be facilely controlled by adjusting the amount of the original graphene oxide-particle composites.