Organic electroluminescent device based on electropolymerized polybithiophene as the hole-transport layer

An ultrathin film of polybithiophene (PBTh), used in organic electrolumines cent (EL) devices, was generated by an electrochemical method with a conduc ting indium tin oxide (ITO) glass as the working electrode. The light-emitt ing layer could be deposited directly onto the PBTh by using spin coating f or fabrication of the organic EL devices. It was found that the film of PBT h as the hole-transport layer for the EL device could effectively raise the EL intensity and efficiency. The EL intensity of the ITO/PBTh/emitting lay er/Al device is about 100 times as strong as that of the ITO/emitting layer /Al device at the same current density of 50 mA/cm(2).