Oxide based highly efficient narrow band red emitting phosphors are still a bottleneck in white LED applications.

Trivalent europium-based monochromatic red light-emitting phosphors are an essential component to realize high-performance smart lighting devices; however, the concentration and thermal quenching restrict their usage. Here, we report a series of efficient Eu3+-substituted Li3Y3BaSr­(MoO4)8 red-emitting phosphors based on a stratified scheelite structure with negligible concentration and thermal quenching. All of the host and phosphor compositions crystallize in monoclinic crystal structure (space group C2/c). All of the phosphor compositions produce narrow-band red emission (FWHM ∼6 nm), which is highly apparent to the human eyes, and lead to exceptional chromatic saturation of the red spectral window. Concurrently, detailed investigations were carried out to comprehend the concentration and thermal quenching mechanism. Absolute quantum yields as high as 88.5% were obtained for Li3Y0.3Eu2.7BaSr­(MoO4)8 phosphor with virtuous thermal stability (at 400 K, retaining 87% of its emission intensity). The light-emitting diodes were constructed by coupling Li3BaSrY0.3Eu2.7(MoO4)8 red phosphor with a near-UV LED chip (395 nm) operated at 20 mA forward bias, and the hybrid white LED (an organic yellow dye + red Li3Y3BaSr­(MoO4)8:Eu3+ phosphor integrated with an NUV LED chip) showed a low CCT (6645 K), high CRI (83) values, and CIE values of x = 0.303; y = 0.368, which indicated that the synthesized phosphors can be a suitable red component for white LEDs. In addition, we have systematically investigated the Sm3+ and Sm3+, Eu3+ activation in Li3Y3BaSr­(MoO4)8 to display the latent use of the system in plant growth applications and establish that the phosphor exhibits orange red emission with an intense deep-red emission (645 nm (4G5/2 → 6H9/2)). The phytochrome (Pr) absorption spectrum well matched the fabricated deep-red LED (by integrating a NUV LED + Li3Y3BaSr­(MoO4)8:Sm3+ and Eu3+ phosphor) spectral lines.

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A sequence of Eu3+ activated Na2Ln4(MoO4)7 [Ln = La, Gd and Y] red phosphors has been synthesized through conventional solid-state method. The phase formation and structural analysis of the synthesized...

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NaSrGd(MoO4)3:Eu3+ red phosphor exhibits higher quantum efficiency (82%) and the fabricated white LED showed 74% CRI and 6823 K CCT.

A series of smart luminescent Eu(iii) complexes (C1 = Eu(DBM)3ligand 1, C2 = Eu(DBM)3ligand 2, C3 = Eu(DBM)3ligand 3, C4 = Eu(DBM)3 ligand 4, C5 = Eu(DBM)3ligand 5) were synthesized by using C1-functionalized phenanthro-imidazole derivatives as the neutral ligands and dibenzoylmethanate (DBM) as the anionic ligand.

A succession of Eu3+ activated Na2Y4(WO4)7 (NYW) red phosphors were synthesised and studied their optical properties in details for white LED, latent fingerprint and plant growth applications. The phosphors crystallised...