Investigation on iodine flow rate in MEH-PPV: I-MWCNT nanocomposite thin film

Abstract

The effect of Iodine flow rate in nanocomposited MEH-PPV:I-MWCNT was investigated by means of electrical, optical and physical characterization. First, 120 mg of MWCNT was doped with 1g of Iodine using thermal chemical vapour deposition method (TCVD). The doping process was done for 1 hour with Iodine flow rate varied from 0.1, 0.3, 0.5, 0.7 and 0.9 l/min. On the other hand, 40 mg of MEH-PPV was stirred for 48 hours in tetrahydrofuran (THF). Next, the I-MWCNT was added to the solution to form nanocomposited MEH-PPV: I-MWCNT solution. The solution was then deposited on glass substrate using spin coating technique. The current-voltage (I-V) measurements were done in dark and under illumination. UV-Vis Spectrometer was used to measure the absorbance and transmittance. For physical properties, the characterizations were done using FESEM and Surface Profiler. From the I-V characteristic, thin film with Iodine flow rate 0.9 l/min gives the best result considering some response it gives towards light. Besides, the sample shows the highest photoconductivity with 2.82×10-3 S/cm. In optical properties, the thin film also gives value 0.89 unit of absorption spectra which is the highest value among other samples. The optimized flow rate will be used to fabricate an active layer of organic solar cell.