Intense green light from a silyl-substituted poly(p-phenylenevinylene)-based light-emitting diode with air-stable cathode

Abstract

A silicon-containing poly(p-phenylenevinylene) derivative, poly[2,5-bis(butyldimethylsilyl)-1,4-phenylenevinylene] (BS-PPV), was synthesized via the Gilch reaction. The polymer is fully solution processable with high thermal stability. The UV-Vis absorption and fluorescent emission spectra demonstrate that BS-PPV is a promising green emissive material for light-emitting device application. Cyclic voltammetric measurements indicate that it can be reversibly n-doped and irreversibly p-doped with the onset oxidation and reduction potentials of 1.16 and -1.81 V, respectively. The HOMO and LUMO energy levels of BS-PPV were estimated to be 5.56 and 2.59 eV, respectively. Single layer devices with the configuration ITO/BS-PPV/Al were fabricated, which showed a turn-on voltage of 6 V and intense green light was observed at around 7.5 V. The performance is better than that of devices fabricated with other silicon-containing PPV-based polymers.