Highly Conductive and Transparent Inkjet-Printed PEDOT:PSS Films

Inkjet printed films of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS PH1000) that combine high electrical conductivity with excellent optical transparency have been obtained through a careful optimization of ink rheology and processing conditions. A $30 \%(\mathrm{v} / \mathrm{v})$ PEDOT:PSS ink in Milli-Q water yielded stable jetting and uniform film deposition at a print resolution of 500 dpi. As-printed films exhibited over $90 \%$ transmittance in the visible wavelength range and a conductivity of $3.4 \mathrm{~S} / \mathrm{cm}$. Post-fabrication treatment with dimethyl sulfoxide (DMSO) yielded conductivity values up to 777 S/cm.