Oxynitride phosphors

Hirosaki et al. [289] reported the blue-emitting Ce -doped LaAl(Si6 2AyN lo-zOz oxynitride phosphor. Blue emission also showed the Ce -activated a-sialon. 

Both, Hirosaki et al. [292, 295] and Zhou et al. [296] reported a green oxynitride phosphor based on Eu -doped P-sialon. Other suitable host lattices for phosphors include MSi202N2 compounds (M = Ca, Sr, and Ba) for example, SrSi202N2 Eu " emits a green color, BaSi202N2 Eu + yields blue-green emission, while CaSi202N2 ... 

Chen WT, Shen HS, Liu RS, Attfield JP (2012) Cation-size-mismatch tuning of photoluminescence in oxynitride phosphors. J Am Chem Soc 134 8022... 

Nakano T, Kawakami Y, Uematsu K, Ishigaki T, Toda K, Sato M (2(K)9) Novel Ba-Sc-Si-oxide and oxynitride phosphors for white LED. J Lumin 129 1654-1657... 

Nitride/oxynitride phosphors have drawn much attention due to their promising optical properties for w-LED applications. Recent studies include MaSisNgiEu (M = Ba, Sr, Ca) [34], CaAlSiN3 Eu2+ [35], P-SiA10N Eu + [36], a-SiAlONiEu - ... 

Table 16.2 Synthesis methods of nitrides and oxynitride phosphors [65]...

Xie R-J, Hirosaki N, Mitomo M, Sakuma K, Kimura N (2006) Wavelength-tunable and thermally stable Li-a-sialon Eu oxynitride phosphors for white light-emitting diodes. Appl Phys Lett 89(24) 241103-241103-241103... 

Dierre B, Xie R-J, Hirosaki N, Sekiguchi T (2007) Blue emission of Ce in lanthanide silicon oxynitride phosphors. J Mater Res 22(07) 1933-1941... 

Low rate solid-electrolyte-based cells For instance, Li/I2 cells used primarily in implantable medical devices are well established. Another example is the developmental all-solid-state Li metal/phosphorous oxynitride (PON)/intercalation cathode cells conceived for use in microelectronic circuits. The PON is a glassy ceramic electrolyte which is stable to over 5 V [25],... 

Lee, C., Akbar, S.A. and Park, C.O. (2001) Potentiometric CO2 gas sensor with lithium phosphorous oxynitride electrolyte. Sens. Actuators B, 76, 591-9. 

The vibrational spectra of phosphorous oxynitride at high pressures... 

The infrared and Raman spectra of phosphorous oxynitride PON, a homologue of silica, have been measured at pressures up to 23 Gpa. The moganite and the a-quartz type crystalline forms of PON have been studied. A correlation has been established between the spectra of PON and those of silica. In the moganite type PON a phase transition has been observed at 4 Gpa. Some preliminary results of an ab initio molecular dynamics simulation are discussed. 

Silicon-based oxynitride and nitride phosphors have encouraging luminescent properties (excitability by blue light, high conversion efficiency, and the possibility of full color emission), as well as a low thermal quenching, high chemical stability, and high potential for use in white LEDs [288, 289]. 

Compared with oxide-, boride-, sulfide-, or phosphate-based phosphors, the study of oxynitride and nitride phosphors is at a very early stage. However, a variety of oxynitride and nitride materials with promising luminescent properties have been discovered recently [290-292]. 

Liu TC, Cheng BM, Hu SF, Liu RS (2011) Highly stable red oxynitride p-SiA10N Pr phosphor for light-emitting diodes. Chem Mater 23 3698... 

Xie RJ, Hirosaki N, Kimura N, Sakuma K, Mitomo M (2007) 2-phosphor-converted white light-emitting diodes using oxynitride/nitride phosphors. Appl Phys Lett 90 191101... 

Xie RJ, Hirosaki N (2007) Silicon-based oxynitride and nitride phosphors for white LEDs-a review. Sci Technol Adv Mater 8 588... 

Chiu YC, Huang CH, Lee TJ, Liu WR, Yeh YT, Jang SM, Liu RS (2011) Eu - -activated silicon-oxynitride Ca3Si204N2 a green-emitting phosphor for white LEDs. Opt Exp 9 A331... 

The demand for efficient WLED phosphors stimulated investigations of new Eu -doped phosphors, e.g., oxynitrides, nitrides, aluminates, and aluminosilicates. Among these, nitrides and oxynitrides have been the subjects of intensive stodies because of their outstanding performances such as quantum yield >80 %, and high thermal and chemical stability [6-8, 22, 24—27]. However, the synthesis of these hosts must be performed at high temperature and high pressure, e.g., 1900 °C and 10 atm N2 atmosphere for Eu -doped -SiAlON [24]. The harsh preparation conditions and high price of raw materials destine these phosphors to be costly. 

Checking over all of the rare earth-doped green to red phosphors with the requirements, we found that none of the rare-earth phosphors can fully meet them. For instance, very recent studies show that either Eu -doped nitride or oxynitride exhibits permanent failure in luminescence and phase structure [33, 34]. When exposed to high-pressure water steam, degradation starts at 150 °C, and the luminescence is quenched very quickly due to the phase decomposition [33]. For long-term applications, it is definitely meaningful to find candidates that can perfectly match all of the requirements. 

Chiu Y-C, Huang C-H, Lee T-J, Liu W-R, Yeh Y-T, Jang S-M, Liu R-S (2011) Eu activated silicon-oxynitride Ca3Si204N2i a green-emitting phosphor for white LEDs. Opt Express 19(103) A331-A339... 

Upon heating, melamine-based salts dissociate, and re-formed melamine volatilizes in a manner similar to pure melamine. However, in the case of melamine salts, a larger portion of melamine undergoes progressive condensation than does pure melamine therefore, the condensed-phase contribution of the salts is larger. If the anion contains phosphorus, the phosphoric acid released will phos-phorylate many polymers and produce a flame retardant effect similar to that of other typical phosphorus-based additives (see above). Melamine condensates and phosphoric acid react further at temperatures above 600° C, where triazine rings are opened and cross-linked. A (PON) type of structure known as phosphorus oxynitride is formed. Phosphorus oxynitride is very thermally stable and in some polymers can contribute to condensed-phase mechanisms. ... 

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