Synthesis And Properties Study Of Red Long Decay Phosphor Ceramics

People started the research on long decay phosphor and ceramics complex materials since 1980s. The most common used material at that time was the sulfured. Since the emergence of many new long decay phosphor materials in the 1990s, it was possible to develop the better performance complex materials. Also, people found this kind of materials in aluminates and silicates systems. Some good complex materials have very steady properties; the illuminate intensity could reach 80% of the phosphors. The decay time can reach 12 hours. The synthesis processes is also simple and easily get produced in the factories. But the demanding of red phosphors is still very high. The development of red long decay phosphor is still under great demand. So the research of red long decay ceramics and glasses is also very limited. People have founded that CaTiO3: Pr3+ is a kind of red long decay phosphor with steady chemical property. CaTiO3: Pr3+ exhibits red luminescence located at x=0.680 and y=0.311 in the CIE coordinates. Furthermore, the CIE coordinates of CaTiO3: Pr3+ is very close to that of the NTSC"ideal red", which makes CaTiO3:Pr3+has great potential value for the actual application of the phosphor. The luminescent intensity of the phosphor which has the nominal composition Ca0.8Zn0.2TiO3:Pr3+, Na+ is higher than CaTiO3: Pr3+. Ca0.8Zn0.2TiO3:Pr3+, Na+ has been synthesized by the solid reaction at high temperature and the luminescent property of Ca0.8Zn0.2TiO3:Pr3+, Na+ has been investigated in this paper.1. We used the high temperature solid state reactions to synthesize the red long decay phosphor of Ca0.8Zn0.2TiO3:Pr3+,Na+. And further we converted them to the luminescent ceramics. We optimized the parameters which influence the luminescent properties such as content of H3BO3, sintering temperature, time and pressure of the pre-reaction.2. A novel Ca0.8Zn0.2TiO3:Pr3+,Na+ nano-particle red long after-glow material were synthesized by sol-gel method, using the red long-lasting phosphorescence properties we can prepare nano-sized titanate luminescent ceramic. The luminescent properties and grain size were systematically studied by fluorescent spectra and scanning electron microscopy. Finding the excitation spectrum of the luminescent ceramic that synthesized by the Ca0.8Zn0.2TiO3:Pr3+,Na+ nano-particle phosphor is a broad band peaking at 338nm and emission spectrum peaking at 616.8nm is due to a transition form 1D2→3H4 of Pr3+ ion. Finding the best technique to prepare the luminescent ceramic that synthesized by the Ca0.8Zn0.2TiO3:Pr3+,Na+ nano-particle phosphor, and the luminescent ceramic synthesized by the nano-particle phosphor were sintered at lower temperatures compared to luminescent ceramic synthesized by the micron-particle phosphor , and showed improved luminescent intensity.3. We made the red long decay glaze of Ca0.8Zn0.2TiO3:Pr3+ and CaS:Eu2+. Both the initial intensity and the decay time are better for the prior material.