Fabrication and photoluminescence properties of ZnO:Zn hollow microspheres

ZnO:Zn hollow microspheres were fabricated on Si(1 0 0) substrates by a direct thermal oxidation process. The formation of ZnO spheres and hollow structures was due to liquid Zn droplets and the high evaporation temperature, respectively. Room temperature photoluminescence showed an ultraviolet band and a broad blue–green–yellow band. White-light emission was clearly observed due to mixtures of complementary colors, e.g. blue–yellow and violet–green. These ZnO:Zn hollow microspheres can therefore be used as white-light emitting materials.