Improved performance of top-emissive polymer light-emitting device with semitransparent Ag cathode with the aid of Au nanoparticles

An efficient top-emissive polymer light-emitting diode (T-PLED) employing Ag as a semi transparent cathode is achieved by adding Au nanoparticles to a phenyl-substituted poly(para-phenylene vinylene) copolymer (HY-PPV). The efficiency of the T-PLED with Au nanoparticles is 3.4 cd/A, which is much higher than that of the T-PLED without such particles (0.15 cd/A). The superior performance of the device is attributed to the balance between the electron and hole currents induced by the Au nanoparticles, which increases the probability of hole-electron recombination. Furthermore, the device's stability in air can be significantly improved because of the use of stable electrodes.