Parameter study of three-dimensional printing graphene oxide based on directional freezing

Graphene is one of the most promising carbon nanomaterial due to its excellent electrical, thermal, optical, and mechanical properties. However, it is still very challenging to unlock its exotic properties and widely adopt it in real-world applications. In this paper, we introduce a new three-dimensional (3D) graphene structure printing approach with pure graphene oxide (GO) material, better interlayer bonding, and complex architecture printing capability. Various parameters related to this novel process are discussed in detail in order to improve the printability, reliability, and accuracy. We have shown that the print quality largely depends on the duty cycle of print head, applied pressure, and traveling velocity during printing. A set of printed samples are presented to demonstrate the effectiveness of the proposed technique along with the optimal parameter settings. The proposed process proves to be a promising 3D printing technique for fabricating multiscale nanomaterial structures. The theory revealed and parameters investigated herein are expected to significantly advance the knowledge and understanding of the fundamental mechanism of the proposed directional freezing-based 3D nano printing process. Furthermore, the outcome of this research has the potential to open up a new avenue for fabricating multifunctional nanomaterial objects.