Facile Fabrication of Random Plasmonic Metasurface Via Azeotropic Solvent-Induced Polymer Template and Its Application in Organic Light-Emitting Diodes

Random plasmonic metasurfaces (RPMs), in which an incident light is diffusely scattered with random phases, have attracted a lot interest due to its broadband optical response. Polymer blend lithography is a widely used nanofabrication method for RPMs. Typically, a high humidity environment is needed to control the phase separation process of polymer blend, which limited the controllability and repeatability of the nanofabrication process. Here, we provide a facile strategy based on azeotropic solvent for phase-separation control of polymer blend. A random nanohole mask is achieved by using H2O/MEK azeotropic solvent at normal humidity (similar to 20%). By depositing silver film on the nanohole mask, we realize a RPM consisting of nanohole-desk units. The scattering spectra centered at 540 nm, 580 nm and 640 nm were realized by changing the size distribution of nanohole-desk units. Furthermore, we used the RPM as an electrode to improve the efficiency of a blue-emission organic light-emitting diode. The facility and scalability of the azeotropic solvent-based nanofabrication method makes this technique a suitable candidate for lots of photonic applications.