Synthesis and Luminescence Properties of Amber Emitting La₇ Sr[Si₁₀ N₁₉ O₃ ] : Eu²⁺ and Syntheses of the Substitutional Variants RE_8-x AE_x [Si₁₀ N_20-x O_2+x ] : Eu²⁺ with RE=La, Ce; AE=Ca, Sr, Ba; 0≤x≤2.

ABSTRACT: The oxonitridosilicate La₇ Sr[Si₁₀ N₁₉ O₃ ] : Eu²⁺ and its substitutional variants RE_8-x AE_x [Si₁₀ N_20-x O_2+x ] : Eu²⁺ with RE=La, Ce; AE=Ca, Sr, Ba and 0≤x≤2 were synthesized starting from REN, SrN/Ca₃ N₂ /Ba₂ N, SiO₂ , amorphous Si₃ N₄ and Eu₂ O₃ as doping agent at 1600 °C in a radiofrequency furnace. The crystal structure of La₇ Sr[Si₁₀ N₁₉ O₃ ] was solved and refined based on single-crystal X-ray diffraction data. La₇ Sr[Si₁₀ N₁₉ O₃ ] crystallizes in the orthorhombic space group Pmn2₁ (no. 31). The crystal structures of the isotypic compounds RE_8-x AE_x [Si₁₀ N_20-x O_2+x ] were confirmed by Rietveld refinements based on powder X-ray diffraction data using the single-crystal data of La₇ Sr[Si₁₀ N₁₉ O₃ ] as starting point. Crystal structure elucidation reveals a 3D network of vertex sharing SiN₄ and SiN₂ (N_1/2-x/4 O_1/2+x/4 )₂ (0≤x≤2) tetrahedra. When excited with UV to blue light, La₇ Sr[Si₁₀ N₁₉ O₃ ] : Eu²⁺ shows amber luminescence with λ_em =612 nm and fwhm=84 nm/2194 cm^-1 , which makes it interesting for application in amber phosphor-converted light emitting diodes.

SUBMITTER: Gamperl L 

PROVIDER: S-EPMC9322326 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature