A double substitution induced Ca(Mg0.8, Al0.2)(Si1.8, Al0.2)O6:Eu2+ phosphor for w-LEDs: synthesis, structure, and luminescence properties

Abstract

A double substitution induced blue-emitting phosphor Ca(Mg_0.8, Al_0.2)(Si_1.8, Al_0.2)O₆:Eu²⁺ (CMAS:Eu²⁺) was successfully synthesized by a solid-state reaction process, and its structure and luminescence properties were investigated in detail. The crystal structure and chemical composition of the CMAS matrix were analyzed and determined based on Rietveld refinements and Energy Dispersive Spectroscopy (EDS). The composition-optimized CMAS:Eu²⁺ exhibited a strong blue light, centered at 446 nm upon excitation at 365 nm with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.144, 0.113). Under 380 nm excitation, the PL emission intensity area of the optimized phosphor was found to be 46.95% of that of the commercial BaMgAl₁₀O₁₇:Eu²⁺ (BAM:Eu²⁺) phosphor and the quantum efficiency of the phosphor is 41.32%. The temperature-dependent PL studies have been investigated which show the thermal stability of the CMAS:Eu²⁺ phosphor compared with that of the CaMgSi₂O₆:Eu²⁺ (CMS:Eu²⁺) phosphor.