▎ 摘　　要

In this work, highly dispersive graphene inks are demonstrated by liquid-phase exfoliation of the bulk graphite crystal in the solvent N-methyl-2-pyrrolidone (NMP). In order to make the inks suitable for inkjet printing, an avenue to tailor the viscosity of the NMP-based ink has been developed through the addition of the organic additive poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS). The use of PEDOT: PSS with graphene inks shows the solutions to exhibit high dispersion densities as deciphered through optical absorbance measurements, while the inkjet printed structures themselves show a uniform microstructure and typical resistivity values of approximately 0.26 m Omega m on average with graphene/PEDOT: PSS inks and can be improved further with the modification of ink properties. PEDOT: PSS as a conductive surfactant enhances the electrical conductivity of graphene patterns, and a viscosity of about 12 cP which is ideal for inkjet printing can be achieved by adding a very small amount (0.25wt. %) of PEDOT: PSS to NMP as compared to higher amounts of nonconductive surfactants like ethyl cellulose needed to obtain similar levels of viscosity. PEDOT: PSS is a workhorse of the organic electronics industry, and this work on graphene/PEDOT: PSS composite inks provides new directions to the organic electronics industry to incorporate two-dimensional layered materials in device platforms. (C) 2017 American Vacuum Society.