Stability of graphene suspensions in an aqueous based multi-component medium

The stability of multi-component graphene-based ink solutions for its optimization and alignment with complex requirements of inkjet printing technologies is considered in the present study. Stable compositions of a four-component suspension (graphene, water, ethanol, and ethylene glycol) were analyzed with the use of Hansen solubility parameters and their experimental corrections. Realization of a set of the stable suspension composition showed that the droplet forming conditions at inkjet printing were fulfilled in all cases. From the point of view of printed layer drying and suppression of the coffee ring effect, it was found that the ethylene glycol concentration has to be lower than 20%. Printing by inks, which fit the optimal composition in all respects, has demonstrated good electrical characteristics, namely, the layer resistance of 3 – 15 kΩ/gama for lines with a 20-40 nm thickness.