Photophysical and energy transfer mechanism studies of Poly (9,9-di-n-octylflourenyl-2,7-diyl)/Fluorol 7GA/Poly [2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] ternary organic blend films

Abstract

Photophysical and energy transfer mechanism of the Poly (9,9-di-n-octylflourenyl-2,7-diyl) (PFO)/Fluorol 7GA (F7GA)/Poly [2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) blend thin films were investigated for potential applications as white organic light emitting diodes. The PFO and F7GA contents in the blends were fixed at 15 mg/ml and 0.5 wt% respectively while MEH-PPV contents were varied from 0% to 1.0 wt%. The blends were stirred and subsequently deposited onto indium tin oxide coated glass substrate to form films using spin coating technique. Due to dipole-dipole interaction and electron-hole migration processes, additions up to 0.3 wt% MEH-PPV resulted in intensified emission of the PFO and F7GA. However, further additions of MEH-PPV produced reversal trend resulted from stronger dipoles interaction, inhibition in excitation of PFO molecules as well as restricted electrons-holes migrations. Despite higher contents, MEH-PPV exhibited almost constant emissions, an indication of energy lost through heat dissipation.