Investigation of Rare Earth Ion Incorporation in Sral2si2o8:Eu3+ Phosphors and Their Photoluminescence Characteristics for Solid-State Lighting

Abstract

All-inorganic silicaluminate-based red luminescence materials are excellent candidates for solid-state lighting applications due to their excellent photoluminescence capabilities. Here, the characteristics of SrAl2Si2O8 phosphors with varying concentrations of Eu3+ doping were investigated, and the SrAl2Si2O8:0.006Eu3+ phosphor with the optimal doping concentration was synthesized using coal gasification slag (CGS) as a raw material. The results demonstrate the successful incorporation of rare earth ions into the crystal lattice, as evidenced by the PL spectrum of Eu3+ ions. Specifically, peaks at 579, 590, 613, and 655 nm correspond to transitions from Eu3+ ions' energy levels of 5D0 to 7F0, 7F1, 7F2, and 7F3, respectively. Among these emissions, red emission dominates at a wavelength of 613 nm with the highest fluorescence intensity. The PL spectra reveal an increase in emission intensity with increasing Eu ion concentration; however, dipole-dipole interactions between fluorescent particles result in fluorescence quenching at higher concentrations. At optimized doping concentration levels, using purified raw materials for synthesis purposes resulted in similar emission performance compared to pure reagent samples. Utilizing CGS products in luminescent material synthesis holds potential for pc-WLED technology.

Keywords: SrAl2Si2O8 phosphors, LED, Coal gasification slag, Rare earth ions, Optical properties