Li24Sr12[Si24N47O]F:Eu2+-Structure and Luminescence of an Orange Phosphor

Horky, Katrin and Schnick, Wolfgang (2017): Li24Sr12[Si24N47O]F:Eu2+-Structure and Luminescence of an Orange Phosphor. In: Chemistry of Materials, Vol. 29, No. 10: pp. 4590-4596

Abstract

The oxonitridosilicate fluoride phosphor Li24Sr12[Si24N47O]F:Eu2+ was synthesized from Si3N4, SrH2, LiNH2, LiF, and EuF3 as dopant in a radio frequency furnace. The crystal structure (space group Pa (3) over bar (no. 205), a = 10.72830(10) angstrom, R-1 = 0.0401, wR(2) = 0.0885, Z = 1) of the host compound Li24Sr12[Si24N47O]F was solved and refined on the basis of single-crystal X-ray diffraction data. Li24Sr12[Si24N47O]F is homeotypic with the nitridosilicate Li2SrSi2N4 as both compounds are characterized by the same tetrahedra network topology, but Li24Sr12[Si24N47O]F is an oxonitridosilicate and contains an additional F site. The implemented F is verified by EDX measurements as well as through calculations with PLATON. Besides, the electrostatic consistency of the refined crystal structure is proven by lattice energy calculations. The Eu2+-doped compound Li24Sr12[Si24N47O]F:Eu2+ shows an orange to red luminescence (lambda(max) = 598 nm;fwhm = 81 nm) under excitation with blue light, which differs from that of Li2SrSi2N4:Eu2+ (lambda(em) = 613 nm;fwhm = 86 nm) due to the additional F site. According to the blue-shifted emission, application in LEDs for sectors with low CRI is conceivable.

• Item Type: Journal article
• Faculties: Chemistry and Pharmacy > Department of Chemistry
• Subjects: 500 Science > 540 Chemistry
• ISSN: 0897-4756
• Language: English