Conductivity Studies of MEH-PPV and MEH-PPV∕Super P Films

Abstract

Poly [2‐methoxy, 5‐(2‐ethyl‐hexyloxy)‐p‐phenylene‐vinylene] (MEH‐PPV) is one of the most widely studied conjugated polymers in the PPV family. MEH‐PPV is a very promising polymer for future applications in organic semiconducting electroluminescent electronic and optoelectronic devices. From our literature search, no previous work has been done on the electrical study of free standing MEH‐PPV films. Freestanding films of pure MEH‐PPV and MEH‐PPV/Super P were obtained by solvent casting method. For the composite film sample, Super P was added to the dissolved polymer. All the films were investigated by a.c. impedance spectroscopy in the temperature range from 300 K to 373 K within 50 mHz‐1 MHz frequency range. The MEH‐PPV/Super P composite had a higher conductivity than the pure MEH‐PPV film. It was observed that the conductivity increased with the increase of temperature for both samples. The Arrhenius plots showed linear relationships between the Log σ and 1000/T parameters and the activation energy of the composite film is less than that of the pure MEH‐PPV.