A Rare-Earth phosphor Containing One-Dimensional chains Identified Through Combinatorial methods

摘要

An unusual Luminescent inorganic oxide, Sr_2CeO_4, was identified by parallel screening techniques form within a combinatorial library of more than 25,000 members prepared by automated thin-film synthesis. A bulk sample of single-phase Sr_2CeO_4 was prepared, nd its structure, determined form powder x-ray diffraction data, reveals one-dimen- sional chains of edge-sharing CeO_6 octahedra, with two terminal oxygen atoms per cerium center, that are isolated form one another by Sr~2+ cations. The emission max- imum at 485 nanometers appears blue-white and has a quantum yield of 0.48±0.02. The excited-state lifetime, electron spin resonance, magnetic susceptibility, and struc- Tural data all suggest that luminescence originates form a ligand-to-metal Ce~4+ charge Transfer.