Genetic algorithm-assisted combinatorial search for new red phosphors of high efficiency at soft ultraviolet excitation

We developed an evolutionary optimization process involving a genetic algorithm and combinatorial chemistry (combi-chem), which was tailored exclusively for the development of light emitting diode (LED) phosphors with a high luminescent efficiency, when excited by soft ultraviolet irradiation. The ultimate goal of our study was to develop oxide red phosphors, which are suitable for three-band white LEDs. To accomplish this, a computational evolutionary optimization process was adopted to screen a Eu3+-doped alkali earth borosilicate system. The genetic algorithm is a well-known, very efficient heuristic optimization method and combi-chem is also a powerful tool for use in an actual experimental optimization process. Therefore the combination of a genetic algorithm and combi-chem would enhance the searching efficiency when applied to phosphor screening. Vertical simulations and an actual synthesis were carried out and promising red phosphors for three-band white LED applications were obtained. (C) 2004 The Electrochemical Society.