Synthesis and Property of the Mn Doped Oxide Red Phosphors in the Calcium Aluminates Koji INOUE, Shinya IWATA and Shinobu HASHIMOTO Recently, the deve

Synthesis and Property of the Mn Doped Oxide Red Phosphors in the Calcium Aluminates Koji INOUE, Shinya IWATA and Shinobu HASHIMOTO Recently, the development of new sulfide-free phosphors with high efficiency is urgently needed for VFDs and FEDs. The fabrication of Calcium Aluminate and the effect of partially substituted Mn on the photoluminescence (PL) were investigated in this research. In the samples annealed at 1923 K for 3 h in air, red photoluminescence was observed.the PL material is expected as a low-cost and red light-emitting diodes. Key words : Red Phosphor, Calcium Aluminates, Photoluminescence(PL), VFD, FED, LED 1-7) CA Eu 2+ CaAl2O4 :Eu 2+ 1) Nd 3+ CaAl 2 O 4 :Eu 2+, Nd 3+ 2) CA2 Ce 3+ CaAl4O7 :Ce 3+ 3) CA6 Mn 4+ CaAl12O19 :Mn 4+ 4) Cr 3+ CaAl 12 O 19 :Cr 3+ 5) C3A Eu 3+ Ca 3 Al 2 O 6 :Eu 3+ 6) C12A7 Eu 2+ Ca12Al14O33 :Ce 3+ 7) 1 C12A7 8) CA Eu 2+ Eu 3+ 3) 14) Nd 3+, Dy 3+, Ti 3+, Er 3+, Ho 3+ Li +, Na +, K + 4), 10)-13) 15) Er 3+ 16) Mn 2+ Ce 3+ 17) Ce 3+ CA2 Ce 3+ Tb 3+ 5) Pr 3+ 18) Mn 4+ 6) Mg 2+ 19) CA6 Cr 3+ 7) Eu 2+ 20) Ce 3+ 21) C3A Eu 3+ 8) Eu 2+ Nd 3+ 22) Cl - 23 C12A7 Ce 3+ 9) Er 3+ 24) Au - 25) LED CaAl12O19 :Mn 4+ CaAl 12 O 19 magneto-plumbite structure CaAl 12 O 19

1 33-34) 1 CaAl12O19 5 Al 3+ Al 3+ 4 5 6 6 (1 ) (1 ) 12 Ca 2+ 5 CaAl12O19 :Mn 4+ 1971 A. Bergstein W.B. White 4)CaAl 12 O 19 CaAl 12 O 19 PL Mn 2+, Mn 3+, Mn 4+ Mn 2+ 511 nm Mn 4+ 657 nm LED CaAl 12 O 19 : Mn 4+ LED LED GaN Y3Al5O12: Ce 3+ GaN 400 nm LED CaAl 12 O 19 : Mn 4+ Mn 4+ 300 nm 500nm LED LED CaAl 12 O 19 : Mn 4+ 9) CaF2 MgF2 Mn 4+ CaAl12O19: Mn 4+ 2 CaAl 12 O 19 : Mn 4+ 10-11) Mg 12-13) Mn CaAl 12 O 19 :Mn 4+ Mn Mn Al 0.5 mol% 20 mol% (CaAl12-xO19: Mnxx = 0.0050.2) Mn Mn Mn CaAl 12-x O 19 : Mn x

1)(CaCO399.99%, 10m) 2)(-Al 2 O 3 99.9%, 5m) 3)()(MnO99.0%, 2-3m) 2 (Electron Spin Resonance ESR) ESR 3 Mn CaAl 12-x O 19 : Mn x (x = 0.000, 0.005, 0.010, 0.020, 0.025, 0.050, 0.100)XRD CaAl12-xO19: Mnx MnO Al2O3 x=0.0010.2 15 1923K3 200K/h 200K/h X X-ray DiffractionXRD (PhotoluminescencePL) Intensity(a.u.) JCPDS card 10 20 30 40 50 60 70 80 Diffraction angle 2θ (deg.) 3 CaAl 12 O 19 MnO Al 2 O 3 CaCO 3 1098K CaO CO2 CaO 1923K CaO Al 2 O 3 Al 2 O 3 4 CaAl 12-x O 19 : Mn x 2= 67

XRD Normalized intensity (a.u.) 67.2 67.25 67.3 67.35 Diffraction angle 2θ (deg.) 4 Mn Ca 2+ = 100 pm, Al 3+ = 53 pm, Mn 4+ = 53 pm, Mn 2+ = 67 pm Mn 2+, Mn 4+ Ca 2+ Mn 2+, Mn 4+ Ca 2+ Al 3+ Mn 2+, Mn 4+, Al 3+ Mn 4+ Al 3+ Mn 2+ Mn 2+ Al 3+ Mn 4+ Al 3+ Mn 4+ Mn 2+ Mn 4+ -Mn 2+ Mn Mn 2+, Mn 4+ Mn 4+ Mn 2+ 5 CaAl12-xO19: Mnx (x = 0.000, 0.005, 0.010, 0.020) PL 6 CaAl 12-x O 19 : Mn x (x =0.020, 0.025, 0.050, 0.100) PL Mn em =655 nm, ex =325 nm 400nm 5 6 4 A2 4 T 1, 2 T 2, 4 T 2 325, 385, 462 nm 2 T 1, 2 E 4 A 2 643, 655 nm

665 nm 2 E 4 A2 4, 12,13) PL 5 66, 19) Mn 4+ - 7 E/B 4 T 1 2 T 2 4 T 2 2 T 1 2 E 8 Mn 2 mol%(x = 0.020) Mn 14) Mn x = 0.020 325 nm 1 2 3 Δ/B 8 Mn 655 nm 4 A 2 9 Mn CaAl 12-x O 19 : Mn x x = 0.000, 0.005, 0.010, 0.020, 0.025, 0.050, 0.100)ESR Intensity (a.u.) x (in CaAl 12-x O 19 : Mn ) x 9 1100 G Fe 3+ 15, 16, x = 0 Fe 3+ x = 0.005 3300 G Mn 2+ 6 17-19))Mn I = 5/2

2I+1 = 6 Mn x = 0.020 1700 G 6 Mn 4+ 16, 18, 20) 3300 G x = 0.005 10 x = 0.005, 0.010, 0.020 3300 G ESR PL x = 0.020 3300 G (1)10 Mn 4+ 16-18 Mn x = 0.025 2000 G 4000 G (1)Mn 4+ 16, 18 x = 0.020 Mn x = 0.050 3300 G 6 3300 G Mn 11 x = 0.025, 0.050, 0.100 ESR Exchange Broadening 39), 45), 46) Mn x = 0.050 Mn CaAl 12 O 19 Al 3+ CaAl12O19 Mn Mn 2+ [x = 0.005-0.010] Mn 4+ (, (1)) [x = 0.020-] Mn 4+ (, ) [x = 0.025-0.100] 1700 G 3300 G Mn 4+ Mn 4+ 1 Al 3+ Ca 2+ Mn 4+ Ca 2+ Mn x = 0.020 x = 0.020 Mn Mn CaAl 12 O 19 Mn Mn 2+ [x = 0.005-0.010] Mn 4+ (, (1)) [x = 0.020-] Mn 4+ (, ) [x = 0.025-0.100]

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