Mechanical properties of graphene-based gyroidal sheet/shell architected lattices

Abstract

AbstractCreating 3D cellular structures out of 2D nanomaterials such as graphene is an active area of research since most realistic applications require multi-functional 3D objects. Graphene aerogels that are taking the topology of stochastic foam microstructures have been extensively studied. Additive manufacturing has shifted the focus from stochastic aerogels to architected 3D graphene lattices (3DGL). In this paper and for the first time, we synthesized, characterized, and mechanically tested 3DGLs with microstructures taking the topology of shell-based gyroid structure and compared their properties to tubular 3DGL. 3DGLs were fabricated using a hydrothermal-assisted dip-coating method based on 3D-printed polymer templates. Effects of number of unit cell, graphene oxide (GO) concentration, and polymer template volume fraction have been investigated. It was found that smaller polymer template volume fraction, smaller unit cell, and larger GO concentration lead to increased mechanical properties. It was found that the mechanical properties of the synthesized gyroid shell-based 3DGLs outperformed tubular and 3DGLs and stochastic graphene aerogels. Furthermore, both gyroidal shell and tubular 3DGLs exhibit stretching-dominated behavior making them ideal for synthesizing stiffer and stronger graphene lattices. This study serves as a guideline for designing multi-functional shell-based lattices made of 2D materials with enhanced mechanical properties for various applications.