11. Plasmonic Coupling Enhanced Absorption and Fluorescence Emission in Thin Film Luminescent Solar Concentrator

This research studied plasmonic composite structures of red dye molecules and gold nanoparticles (Au NPs) for thin film luminescent solar concentrator (LSC). The plasmonic coupling between the red dye molecules and Au NPs was established through controlled spacing, surface plasmon resonance enhanced local photon mode density, and multiple excitation of red dye molecules. The plasmonic composite thin film LSCs were fabricated using spin coating. Two types of structures, homogenous and multilayer layered plasmonic composite thin film LSCs, were studied. In the homogenous LSC, the Au NPs doping concentration distribution controlled spacing between Au NPs and red dye molecules. The multilayered plasmonic composite, transparent polymer spacer layer of 0.0, 30 ± 5 and 60 ± 5 nm was placed between the red dye molecules and Au NPs film to control volume of red dye molecules experienced plasmonic interaction. Spectroscopic and confocal microscopic characterizations probed localized and macroscopic behavior of plasmonic composite structurers. The thin film LSC edge emission measurements assessed the plasmonic coupling enhanced emission for thin film LSCs and their correlation established optimum plasmonic coupling between red dye molecules and Au NPs. Plasmonic interaction improved optical absorption of the plasmonic composite thin film LSC by ~12% moreover independent spacer layers thickness. The fluorescence emission of plasmonic composite structure enhanced by 13, 20, and 25% for spacing layer 0.0, 30 ± 5 and 60 ± 5 nm, respectively. The electrical characterization of this plasmonic thin film LSC followed optical characterizations.