Layer-by-Layer Method to Prepare Three-Dimensional Reduced Graphene Materials with Controlled Architectures Using SiO2 as a Sacrificial Template

Graphene is a two-dimensional (2D) carbon allotrope that has been used for developing three-dimensional (3D) carbon architectures. Such materials are in the spotlight due to their high surface area and tunable pore size, which can be used for many applications including catalysis, depollution, and energy storage. However, controlling the morphology and pore size of the 3D carbon architectures remains a challenge. Herein, the preparation of a 3D material based on reduced graphene oxide is reported via a layer-by-layer method coupled with a sacrificial template method. Spherical SiO2 particles were used as templates, covering them with graphene oxide (GO) at room temperature and using water suspensions. The coated particles undergo thermal reduction followed by acid treatment resulting in a 3D carbon architecture with well-defined morphology. This method offers important advantages such as pore size tuning, controlled morphology, large-scale production, and the possibility to be extended with different covering materials.