Tunable, Ligand-Based Emission from Inorganic−Organic Frameworks: A New Approach to Phosphors for Solid State Lighting and Other Applications

• Published in: Chemistry of materials Vol. 22; no. 7; pp. 2255 - 2260
• Main Authors: Furman, Joshua D, Warner, Alina Y, Teat, Simon J, Mikhailovsky, Alexander A, Cheetham, Anthony K
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 13.04.2010
• Subjects: CALCIUM COMPLEXES; DICARBOXYLIC ACIDS; EMISSION; Hybrid Inorganic/Organic Materials; LIGHTING SYSTEMS; MATERIALS SCIENCE; MOLECULAR STRUCTURE; Optical Materials (including Non-Linear Optic, Photonic, and Optoelectronic Materials); PHOSPHORS; STRONTIUM COMPLEXES; Structural Characterization (including AFM, NMR, X-ray Diffraction, etc.); SYNTHESIS; VISIBLE RADIATION
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm9030733

Two dense inorganic−organic frameworks were prepared using the intrinsically luminescent organic ligand 9-fluorenone-2,7-dicarboxylic acid (H2FDC) in combination with the alkaline earth metals calcium and strontium. Ca(FDC)(H2O)2 (1) and Sr(FDC)(H2O)5·2H2O (2) were prepared hydrothermally and both adopt three-dimensional framework structures. They absorb strongly between 380 and 460 nm and show broad visible emission with peaks at 503 and 526 nm, respectively. Structure 1 shows a quantum yield at room temperature of 7.8% which increases to 15% at −196 °C, while structure 2 shows a room temperature quantum yield of 2.8%, increasing to 3.3% at −196 °C.