Zn-xMoO,xPr+ deep red-emitting.docVIP

Luminescent properties of novel Zn0.98MoO4: Pr3+0.02 deep red-emitting phosphor synthesized via a co-precipitation route for white light-emitting diodes Da-ming Ye(叶达明), College of Physics Electronic Information, Yunnan Normal University, Kunming 650500, China Keywords: Zinc Molybdate; trivalent praseodymium(Pr3+); red phosphors; WLEDs Abstract: Zn0.98MoO4:Pr3+0.02 pale green powder was synthesized by a co-precipitation method and characterized by powder X-ray diffraction pattern as well as photoluminescence measurements. These results show that Zn0.98MoO4:Pr3+0.02 phosphor has triclinic structure and the strong deep red line at 661nm corresponds to the hypersensitive 3P0→3F2 transition of Pr3+. Introduction Phosphor-converted white light-emitting diodes (pc-WLEDs) [1] as so-called the fourth generation solid-state light source show mangy advantages such as long lifetime, high luminescent efficiency, low power consumption, non-pollution, etc and are gradually replacing conventional incandescent and fluorescent lamps. Generally, there are three ways to generate white light. Either way, red phosphors are urgent and necessary for obtaining white light with high color rendering index. Pr3+-doped materials have many technological applications such as red-emitting phosphors, scintillators, fiber laser amplifier, visible lasers and mid-infrared laser, quantum cutting (photon cascade emission), tunable UV and vacuum UV lasers, up-conversion lasers as well as the agents improving solar cells efficiency attributed to the high energetic interconfigurational (4f2?4f15d1) and intraconfigurational (4f2?4f2) intricate transitions of the Pr3+ ion[2] which has rich emission spectral lines extending from the ultraviolet (UV), through the visible, to the near-infrared regions. It is worth noting that praseodymium is much cheaper than europium. Among all molybdates, wolframite-type metal molybdates (MMoO4, M=Zn, Co) are widely applied in photoluminescence, microwave applications, cata