Quick Screening Provides Key to New Luminescent Materials

Researchers have long sought new compounds for ultraviolet-excited phosphors -- important for the development of flat panel displays and lighting. Because there are no reliable theories to predict the relation between composition and efficiency, scientists discovered the fewer than 100 commercial phosphor materials through time-consuming one-by-one synthesis and testing. This proved daunting for researchers, considering that there are more than 25,000 inorganic materials classified as candidates for new phosphors. Typical phosphors are inorganic powders consisting of a poly-crystalline host doped with rare-earth or transition metal ions.
Now a group of engineers from Symyx Technologies in Santa Clara, Calif., has presented a new approach to calculating the usefulness of different compounds. The team has implemented technology that provides high-speed, automated synthesis and screening combinations of more than 25,000 different materials. The highly efficient screening process has led to the discovery of a red phosphor, Y_0.845A_0.070La_0.060Eu_0.025V0₄. The new phosphor has a higher quantum efficiency than most commercially available red phosphors.