Template-Assisted Synthesis of Dy3+-Doped Bi2SiO5 Nanospheres with Excellent Luminescence and Thermal Stability.

Abstract

In this work, Dy³⁺-doped Bi₂SiO₅ nanoparticles with uniform spherical morphology and narrow size distribution have been successfully synthesized using a facile template-assisted approach. The effects of sintering temperature and Dy³⁺ doping concentration on the phase composition, morphology, and luminescence properties of Bi₂SiO₅:Dy³⁺ nanophosphor are systematically investigated through X-ray diffraction, scanning electron microscopy, and photoluminescence (PL) spectroscopy. X-ray diffraction results confirm that the synthesized Bi₂SiO₅:Dy³⁺ nanospheres exhibit a pure tetragonal phase. Meanwhile, the phosphor particles are composed of monodisperse nanospheres with an average diameter of approximately 265 nm. Upon excitation at 388 nm, intense photoluminescence is noted in the blue (⁴F_9/2→⁶H_15/2) and yellow (⁴F_9/2→⁶H_13/2) spectral regions due to the characteristic emissions of Dy³⁺ ions. Temperature-dependent PL spectra reveal that the optimized Bi₂SiO₅:2.5%Dy³⁺ nanospheres maintain extraordinary luminescence thermal stability, retaining 81.0% of its emission intensity at 423 K compared to 303 K. The phosphor also showed remarkable color stability, with CIE chromaticity coordinates shifting minimally from (0.377, 0.413) at 303 K to (0.373, 0.407) at 423 K. This newly developed Bi₂SiO₅:Dy³⁺ nanospheres exhibit commendable PL properties, enabling them as promising candidates for yellow phosphors in LEDs and display applications.