Photoconductivity of nanocomposited MEH-PPV: CNTs thin film for organic solar cells application

Our work focused on nanocomposite MEH-PPV: CNTs prepared by spin coating technique. The MEH-PPV which is in powder form (commercially available) was weighted and then dissolved in Toluene and stirred for 48 hours. Then, a small amount of CNTs were added to the MEH-PPV solution. It is sonicated for 1 hour to ensure that CNTs is well dispersed in the MEH-PPV solution. The addition of CNTs in the MEH-PPV solution yields a nanocomposite MEH-PPV:CNTs solution. The electrical properties of the thin films were studied to identify whether the nanocomposite thin films have ohmic capability or vice versa. Optical properties of the thin films were characterized using UV-VIS-NIR spectrophotometer. From the current-voltage characteristics it can be seen that there is no photo response when light is illuminated to the sample of MEH-PPV blend CNTs. The highest conductivity is at 2 wt% concentration of CNT with 100k Sm^-1. It also gives the highest value of absorption spectra which is 0.25 for nanocomposite MEH-PPV: CNTs thin film.