Graphene-based 3D lightweight cellular structures: Synthesis and applications

Ultralight three-dimensional (3D) cellular architectures are both a challenge and an opportunity for those academic and industrial applications involved with high performance material design. The challenges have been accessed by employing a variety of materials. Accordingly, graphene has shown greatest potential by virtue of its unique chemical, thermal, electronic, and mechanical properties for applications ranging from structural materials to energy storage/conversion devices. In this review, we highlight recent efforts and advances made in the implementation of graphene-based 3D cellular architectures, especially focusing on the ultralight density region (<10 mg·cm⁻³). First, we reviewed the synthetic approaches for generating graphene-based 3D lightweight cellular structures according to the criteria of closed-cellular structures (CCSs) or open-cellular structures (OCSs) whether cell faces between constituent unit cells exist or not, respectively. These structural differences could lead to discerning physical properties, such as in mass transport across pores, heat/electron transfer through graphene framework, and various modes in mechanical deformation. We then collectively introduce recent achievements for representative applications utilizing different types of cellular structures such as flexible electronics, energy storage/conversion systems, fluid absorption, mechanical dampers, and sensors. Finally, we highlight the future perspectives of graphene-based lightweight cellular structures to surpass existing technological challenges.