SPFGO effects on the electroluminescence and photovoltaic response in conjugated polymers

Abstract

This paper studies the influence of poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV) on solution-processable functionalized graphene oxide (SPFGO) composite film-based organic light emitting Diode (OLED) and organic photovoltaic (OPV) performance for different SPFGO concentrations. There is a strong quenching of photoluminescence when MEH-PPV is doped with SPFGO, which means there is a strong transfer of electron and energy between MEH-PPV and SPFGO. Doping SPFGO in MEH-PPV can improve the performance of OLED at low concentration, and the performance will be the best when the concentration of SPFGO is 0.2%; however, the performance of OPV remains unchanged. The performance of OPV could be improved by high doping concentration of SPFGO, the performance will be the best when the concentration of SPFGO reaches 15%, and there is a quenching in the electroluminescence (EL) of OLED. As shown in the statistics of the experiment, SPFGO can increase the injectivity of carriers, and when the SPFGO is of low concentration, it can increase the luminous intensity of OLED and reduce the threshold voltage. SPFGO can act as an electron acceptor, and when the concentration of SPFGO is high, the exciton dissociation at MEH-PPV/SPFGO interface can be improved, and the performance of OPV can be also improved. Therefore, the concentration of SPFGO should be the main factor in adjusting the performance of OLED and OPV separately.