Controlling surface porosity of graphene-based printed aerogels

The surface porosity of graphene-based aerogels strongly influences their performance in applications involving mass transfer. However, the factors determining the surface porosities are not well-understood, hindering their application-specific optimisation. Here, through experiments and hydrodynamic simulations, we show that the high shear stress during the graphene-based aerogel fabrication process via 3D printing leads to a non-porous surface. Conversely, crosslinking of the sheets hinders flake alignment caused by shearing, resulting in a porous surface. Our findings enable fine control of surface porosity of printed graphene-oxide aerogels (GOA) through regulation of the crosslinking agents and shear stress. Using this strategy, we demonstrate the performance advantages of GOA with porous surface over their non-porous counterpart in dye adsorption, underscoring the importance of surface porosity in certain application scenarios.

Automated summary

The surface porosity of graphene-based aerogels plays a crucial role in applications involving mass transfer. Through experiments and simulations, it is found that high shear stress during the fabrication process leads to a non-porous surface, while crosslinking of the sheets results in a porous surface. Controlling the surface porosity of printed graphene-oxide aerogels (GOA) can be achieved by regulating the crosslinking agents and shear stress. The study demonstrates the performance advantages of GOA with porous surface in dye adsorption, highlighting the importance of surface porosity in specific applications.