Combinatorial search for advanced luminescence materials

Phosphors are key materials in fluorescent lighting, displays, x-ray scintillation, etc. The rapid development of modern photonic technologies, e.g., mercury-free lamps, flat panel displays, CT-detector array, etc., demands timely discovery of advanced phosphors. To this end, a combinatorial approach has been developed and applied to accelerated experimental search of advanced phosphors and scintillators. Phosphor libraries can be made in both thin film and powder form, using masking strategies and liquid dispensing systems, respectively. High-density libraries with 100 to 1000 discrete phosphor compositions on a 1"-square substrate can be made routinely. Both compositions and synthesis temperatures can be screened in a high-throughput mode. In this article, details on the existing methods of combinatorial synthesis and screening of phosphors will be reported with examples. These methods are generic tools for application of combinatorial chemistry in the discovery of other solid state materials. A few highly efficient phosphors discovered with combinatorial methods have been reproduced in bulk form and their luminescent properties measured.