Investigation on Annealed CNTs to the Electrical and Optical Properties of Nanocomposited MEH-PPV: CNTs Thin Film

Abstract

Our research focused on the organic semiconductor layer of MEH-PPV blend CNTs to investigate the electrical and optical properties with different composition ratio of CNTs. The composition ratios are from 0, 1, 2, 3 and 4 wt%. The solvent used for dissolving the MEH-PPV is toluene which is an aromatic solvent. The CNTs are annealed before mixing it to the MEH-PPV solution at 450οC for 30 minutes. This is to ensure that all of the impurities in the CNTs are totally removed. After blending the CNTs with the MEH-PPV, the nanocomposite is then deposited on a glass substrate by spin coating technique. The optical properties of the thin film were characterized by using UV-VIS spectrometer to analyze the absorbance and transmittance of the thin film. The electrical properties characterization is done using two point probes to measure the current in dark and under illumination condition. The highest value of conductivity is at 4 wt% concentration of CNTs with 0.02738 Sm-1. It can also be observed that the thicknesses of the thin films decreased from 0 wt% to 4 wt%. The highest value of absorbance is at 0 wt% with the value of 0.35. The absorbance peak tends to shift to a shorter wavelength with respect to the main absorbance (0 wt %) as reference sample. Transmittance of the thin film showed improvement from 40 to 70 T%.