Fig. 3: Degradation of electron transport and photovoltaic performance during light exposure process.

a Electron current density × film thickness (J × d) of devices as a function of the applied electric field for fresh and aged (standard 1-Sun illumination for 70 h) of PM6:PY-V-γ and PM6:Y6 electron-only devices; b PM6:PY-V-γ and PM6:Y6 electron-only devices in (a) as a function of the standard 1-Sun illumination time; c normalized PCE of PM6:PY-V-γ and PM6:Y6 organic solar cells as a function of the standard 1-Sun illumination time; and d fresh and aged (standard 1-Sun illumination for 70 h) PM6:PY-V-γ and PM6:Y6 electron-only devices with various acceptor weight fractions.