The 80±100 nm polyfluorene films were deposited by spinning a solution of 15 mg/mL polyfluorene (Cambridge Display Technology) in p-xylene onto the films (TMDC, TMDC subjected to O 2 plasma, or PEDOT±PSS).
Fabrication of 3.1 mm 2 pixels (8 per device) was subsequently completed in a N 2 glovebox without exposure to air. Calcium/aluminum electrodes (100 nm/100 nm) were evaporated through a shadow mask at a base pressure of <10 ±6 mbar.
Characterization: XRD measurements were performed on a CPS-120 powder diffractometer assembled by spectrolab using Inel hardware and software. The X-ray beam was Cu Ka.
XPS measurements were carried out with an AXIS-HS Kratos set-up, using an Al Ka X-ray source and pass energies ranging from 20 eV to 80 eV.
Ellipsometry measurements were performed on a J. A. Woolam M-2000 diode array rotating compensator ellipsometer with a xenon lamp source (245±900 nm). Modeling was performed using J. A. Woolam Co. WVASE32 software.
Tapping mode AFM Measurements were performed using a NanoScope IIIa Dimension 3100 (Digital Instruments Inc, Santa Barbara, CA).
JVL characteristics were collected under vacuum (10 ±1 mbar) using a Keithley 230 voltage source together with a Keithley 195 digital multimeter; the luminescence output was simultaneously measured using a calibrated Si photodiode collecting 0.1 sr in the forward direction.