Control of microstructure to prepare compressible graphene aerogel via ice template

The microstructure of graphene aerogel (GA) plays a crucial role in determining its performance. However, challenges persist in simplifying and enhancing control over the microstructure of GA. In this study, we introduce a novel bidirectional freeze-casting method, allowing for the preparation of GAs with three different microstructures. Notably, the GA with concentric ring structure exhibits exceptional compressibility and fatigue resistance in both axial and radial directions, capable of undergoing 5000 compression-recovery cycles at 90% strain and 70% strain, respectively. In-situ SEM characterization provides insights into the energy dissipation mechanism during compression processes. GA with radial microstructure demonstrates an impressive absorption capacity ranging from 165.82 to 369.47 g/g. Moreover, the GA with concentric ring microstructure displays non-linear resistance changes with strain under both axial and radial compression. These GAs demonstrate significant potential applications in environmental remediation and flexible electronics.