AUTHOR=Wu Lingjun , Wang Wei , Zhao Haitao , Gao Libo , Lu Jibao , Sun Rong 

TITLE=A Molecular Dynamics Simulation Study: The Inkjet Printing of Graphene Inks on Polyimide Substrates

JOURNAL=Frontiers in Materials

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2021.769071

DOI=10.3389/fmats.2021.769071

ISSN=2296-8016

ABSTRACT=Inkjet printing-based 2D materials for flexible electronics aroused much interest due to its highly low-cost customization and manufacturing resolution. It is however less to have an enough investigation and essential understanding of the surface adhesion affected by the printing parameters at atomic-scale. Herein, we conducted systematic molecular dynamics simulation investigating the inkjet printing of graphitic inks on polyimide substrates under various conditions. Simulations under different temperatures, inkjet velocities, mechanical loading such as pressure and deformation are performed. The results show that best adhesion is achieved in the plasma-modified polyimide/graphene-oxide (mPI/GO) interfacial system (the interaction energy (Ein) between mPI and GO is ca. 1.2 times than with graphene). The adhesion strength decreases with increasing temperature, and higher inkjet velocities lead to both larger impact force as well as interfacial fluctuation, while the latter may result in greater interfacial instability. When loaded with pressure, the adhesion strength reaches a threshold without further improvement as continuing compacting of polymer slabs can hardly be achieved. The detachment of the interfaces was also explored and mPI/GO shows better resistance against delamination. Hopefully our simulation study paves the way for future inkjet printing-based manufacturing of graphene-based flexible electronics.