An ultra-thin gold nanoparticle layer modified cathode for the enhanced performance of polymer light emitting diodes

Abstract

The enhanced performance of polymer light emitting diodes has been achieved by embedding an ultra-thin gold nanoparticle layer on the cathode. The performance of devices could be optimized simply by adjusting the thickness of gold, which exhibited the improved brightness from 17k cd m⁻² to 20k cd m⁻² and the enhanced luminous efficiency from 15.4 cd A⁻¹ to 18.3 cd A⁻¹, when a greenish emissive polymer P-PPV was applied as an emissive layer. The experimental results show that it is mainly attributed to the decreased holes and the increased electrons, resulting in the balanced electron–hole recombination and the shifted light emitting profile to the anode. The results demonstrate that gold nanoparticles constitute a feasible and effective route for achieving high-performance polymer optoelectronic devices through their electric properties.