Thin large-area graphene oxide film formation from multicomponent suspensions

In this study, we investigate the influence of additional organic components of the graphene oxide suspension on wetting properties of PET substrates. Insufficient wettability of polymer substrates is one of the important challenges for flexible electronic devices based on graphene derivatives. In our research we showed a possibility to enhance the wettability of graphene oxide suspensions by incorporating additional organic components. Based on solubility parameters we choose N-methylpyrrolidone, dimethylacetamide, and two types of lacquer paint thinners as additional components. In all instances, we observed a successful reduction in the contact angle.
We also analyzed the drying time of multicomponent dispersions. Depending on the component ratios and the type of dispersion, the drying time can vary significantly, ranging from 3 to over 40 times, that is important for choosing the optimal deposition method. The stability of dispersions containing N-methylpyrrolidone and dimethylacetamide was confirmed for more than two months, while dispersions with lacquer paint thinners remained stable for approximately 1.5 months.
We showed possibility of formation of large-area graphene oxide films on PET substrate with the use of multicomponent graphene oxide suspensions. In case of concentrations higher than 0.9 mg/ml we observed formation of uniform films that covers the whole substrate.