Synthesis of novel K₂Sr(MoO₄)₂:Sm³⁺ orange–red phosphors and application to high color rendering index white LEDs

A newly synthesized orange–red-emitting phosphor, K₂Sr(MoO₄)₂:Sm³⁺, was produced for the first time through high-temperature solid-state synthesis methods. Detailed analysis was conducted on the phase purity, morphology, and luminescence properties of the synthesized phosphors. The K₂Sr(MoO₄)₂:Sm³⁺ phosphors let forth orange–red light when excited at 403 nm because of the ⁴G_5/2 → ⁶H_9/2 transition. The optimal doping concentration of the K₂Sr(MoO₄)₂:xSm³⁺ phosphor was found to be x = 3 mol%. The chromaticity coordinates of K₂Sr(MoO₄)₂:3 mol% Sm³⁺ were (0.617, 0.381) with a corresponding high color purity of 99.8%. This prepared w-LED exhibited an exceptional color rendering index (CRI) of 90, while maintaining a suitable correlated color temperature (CCT) of 5825 K and CIE color coordinates were (0.325, 0.327). Hence, K₂Sr(MoO₄)₂:Sm³⁺ phosphors are desirable options for creating w-LEDs and lighting based on near-ultraviolet (NUV) chips. Their unique properties show significant potential for enhancing the performance of solid-state lighting.