Enhancing luminescent down-shifting of Eu-doped phosphors by incorporating plasmonic silver nanoparticles for silicon solar cells

Abstract

This study experimentally demonstrated enhanced fluorescence emissions from luminescent down-shifting (LDS) Eu-doped phosphors under the effects of localized surface plasmon resonance (LPSR) from silver nanoparticles (Ag NPs). The plasmonic effects of the Ag NPs was examined in terms of plasmon-enhanced Raman scattering and plasmonic absorption. The fluorescence emission of the Eu-doped phosphors was examined in terms of photoluminescence (PL). Overlap between the plasmonic absorption band of Ag NPs and the PL emission band of Eu-doped phosphors increased fluorescence emissions by enhancing excitation. This study also developed an optical process model describing LSPR (Ag NPs), LDS (Eu-doped phosphors), and plasmon-enhanced fluorescence (PEF; Eu-doped phosphors with Ag NPs) on silicon solar cells. PEF was experimentally confirmed in terms of PL, external quantum efficiency (EQE), and photovoltaic current–voltage measurements. Compared to the cell with only an anti-reflection layer of SiO2/SOG, the inclusion of Ag NPs with the Eu-doped phosphors enhanced the PL emission intensity by 1.1243 times at a wavelength of 514 nm and also improved the EQE response by 8.3% (from 57.28% to 62.05%) and conversion efficiency by 7.1% (from 12.04% to 12.89%).