Ultralight‐Weight Graphene Aerogels with Extremely High Electrical Conductivity

The integration of 2D graphene sheets into a porous and macroscopic structure is extremely attractive for application in several electrochemical fields. In this regard, for the first time, the synthesis of 3D graphene aerogels is reported by using a rapid, easy, cost‐effective, and scalable at industrial level methodology. These aerogels integrate the intrinsic properties of graphene with a high pore volume. To achieve this ultraporous graphene network, resorcinol/formaldehyde polymer with controllable porosity is employed as a binder and a cross‐linker material, and a graphene oxide solution provides the graphene building blocks. Two series of materials with and without catalyst for resorcinol/formaldehyde reaction and with different synthesis conditions and graphene contents are studied. The resulting graphene aerogels present low density, large macroporosity, and electrical conductivity values as high as 852 S m−1, with 97.58% of porosity, which is the highest value of electrical conductivity reported so far in the literature for ultralight‐weight graphene aerogels. Here a new material that combines a very high electrical conductivity (>850 S m−1) with an extremely high porosity (>97%) is discussed. These materials are obtained by a microwave‐assisted process that greatly reduces synthesis times. This combination of properties greatly exceeds those known so far in the literature for any material, widening the possible applications.