▎ 摘　　要

Three-dimensional (3D) graphene has become an area of great interest due to its unique properties, and different synthesis routes and structures have been reported in the literature. However, the challenges of retaining high quality, scaling up and improving economic feasibility are apparent. Here we describe 3D graphene sheet (3DGS), which is a novel, electrically conductive and porous 3D graphene material that addresses some of these challenges. Due to the combination of polymer binders and a casting technique, scale up for this material is possible. The 3DGS reported in this work can be described as a seamless and freestanding assembly with low structural defects, electrical conductivity of 14.71 S/cm and reasonable mechanical integrity. This material exhibits an average density of 21.65 +/- 1.49 kg/m(3) and a mesoporous structure with a specific surface area of 16.5m(2)/g. The Chemical Vapor Deposition (CVD) synthesis and the cast catalyst preparation method is simple and versatile in terms of tuning the material properties such as areal density and electrical conductivity. These and other properties of 3DGS enable its use in many applications, especially as binder-free, flexible electrodes and current collectors for energy storage devices and sensors.