Plasmon-Enhanced Fluorescence of Phosphors Using Shell-Isolated Nanoparticles for Display Technologies

Plasmonics has attracted considerable interest due to its promising applications in optical technology, with particular attention recently being focused on the plasmon-enhanced emission of phosphors. Phosphor is an important component of phosphor-converted LEDs (pc-LEDs) which are deemed the next-generation display lighting source, but it suffers from low intrinsic efficiencies. Plasmonics can be used to enhance the optical properties of phosphors for LEDs. However, energy-transfer processes from the phosphor to the plasmon-enhancing metal can significantly quench fluorescence signals, limiting the applications of such phosphors. Herein, the fluorescence of a commercial phosphor was enhanced by using shell-isolated Ag nanoparticles (Ag-SHINs) "satellite structures" (phosphor@Ag-SHINs). As a universal strategy, large fluorescence enhancements were achieved by coupling phosphor fluorescence wavelengths with the localized surface plasmon resonance (LSPR) wavelength of structurally optimized Ag-SHINs satellites. Three-dimensional finite difference time domain (3D-FDTD) simulations and lifetime tests showed the enhancement in phosphor fluorescence signals resulted from acceleration of spontaneous emission rates by the local optical density of states (LODS) generated by the Ag-SHINs satellites. This work provides an effective avenue for enhancing phosphor fluorescence signals with potential practical applications in display technologies.