Efficiency Improvement in Polymer Light‐Emitting Diodes by “Far‐Field” Effect of Gold Nanoparticles |
| |
Authors: | Xiaoyan Wu Linlin Liu Zhicong Deng Li Nian Wenzhuo Zhang Dehua Hu Zengqi Xie Yueqi Mo Yuguang Ma |
| |
Affiliation: | 1. Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, P.R. China;2. State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun, China |
| |
Abstract: | The “far‐field” effect of metal nanoparticles (NPs), when chromophores localized nearby metal NPs (typically the distance >λ/10), is an important optical effect to enhance emission in photoluminescence. The far‐field effect originates mainly from the interaction between origin emission and mirror‐reflected emission, resulting in the increased irradiative rate of chromophores on the mirror‐type substrate. Here, the far‐field effect is used to improve emission efficiency of polymer light‐emitting diodes (PLEDs). A universal performance improvement is achieved for the full visible light (red, green, blue) PLEDs, utilizing gold (Au) NPs to modify the indium tin oxide (ITO) substrates; this is shown by experimental and theoretical simulation to mainly come from the far‐field effect. The optimized distance, between the NPs and chromophores with visible light emission ranging from 400 to 700 nm, is 80–120 nm. Thus the scope of the far‐field may overlap the light‐emitting profile very well to enhance the efficiency of optoelectronic devices. The 30–40% enhancement is obtained for different color‐emitting materials through distance optimization. The far‐field effect is demonstrated to enhance device performance for materials in the full‐visible spectral range, which extends the optoelectric applications of Au NPs. |
| |
Keywords: | distance dependence exciton distributions light‐emitting profiles metal‐enhanced fluorescence p‐type semiconducting polymers |
|
|