Discovery and optimization of new ZnO-based phosphors using a combinatorial method

The combinatorial method, which, was exclusively employed for the drug discovery until recently, has invaded the field of inorganic materials and is becoming a key technology in materials science today. Phosphors, with their diversity of possible mechanisms of luminescence, represent a typical example of a field where the combinatorial approach promises to be especially fruitful. Here, we present the results of systematic combinatorial exploration of different binary and ternary ZnO:dopant systems, which resulted in identification of bright luminescence in ZnO:(Y,Eu), ZnO:V, ZnO:W, and ZnO:(W,Mg) systems. Careful "zooming in", i.e., fabrication and screening of more detailed libraries near the identified promising compositions, allowed us to find optimum phosphor compositions for the above-mentioned systems. The efficiency of the new phosphors in low-voltage cathodoluminescence is high and promises their prospective use in advanced flat panel display and lighting applications.