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Highlights • A new orange phosphor GGAON 0.5 :Ce3+ with sufficient red component was synthesized. • No decay in the 10 microsecond is the key feature applied in AC-circuit directly. • Self-packed LED lamp emits warm white light with high rendering index. Abstract Solid solution phosphors Gd 3 Ga 2 (Al 3- y Si y)(O 12- y N y):Ce3+ were synthesized by introducing [Si4++N3–]/[Al3++O2–] co-substitution into the lattice of Gd 3 Ga 2 Al 3 O 12 :Ce3+. Gd 3 Ga 2 Al 3 O 12 :Ce3+, characteristic as outstanding light yield (about 50–60 kPh/ MeV), and has been applied in computer tomography (CT), positron emission tomography (PET) nuclear medical detector, et al. With the increase of y value, the coordination environment around Gd3+(Ce3+) shrinked, which were confirmed by combining techniques of structure refinement, energy- dispersive spectrum, elements distribution mapping. As a result, stronger 5 d orbital nephelauxetic effect (ε c) and bigger 5 d energy level splitting (ε cfs) were induced. Thus resulting in longer wavelength of excitation and emission from Ce3+, and broadening of emission spectra. The typical sample Gd 2.95 Ga 2 Al 2.5 Si 0.5 O 11.5 N 0.5 :0.05Ce3+ (GGASON 0.5 :Ce3+) exhibits sufficient red component and persistent luminescence(>10 ms), enables fabrication of warm white light suited for alternating-current (AC) when combined with blue light chip (460 nm). [ABSTRACT FROM AUTHOR]

At the synthesis temperature of α-cordierite (α-Mg 2 Al 4 Si 5 O 18), compositions of Mg 2+ x Al 4-2 x Si 5+ x O 18 crystallized as β-cordierite (β-Mg 2+ x Al 4-2 x Si 5+ x O 18) when x is over 0.2. By doping Eu2+ into optimal host β-Mg 2.25 Al 3·5 Si 5·25 O 18 (β-MASO), a series of novel cyan luminescence materials were obtained. Excitation spectra ranged from 250 to 450 nm, and peaked around 365 nm. Under wavelength of excitation peaks, emission maximum of series samples moves from 464 nm to 485 nm with the increase of Eu2+. Decay behaviors and Gaussian multiple fitting results of emission spectrum, consistent with crystal analysis that the Eu2+ occupy three kinds of crystallographic sites. For representative sample β-MASO:0.02Eu2+, internal quantum efficiencies (η 1) is about ∼56.96%, and its emission intensity remains at 66% of initial intensity at 150 °C. Under excitation at UV (365 nm) lamp, the white light with warm tune was obtained by mixing β-MASO:0.02Eu2+ with red CaAlSiN 3 :Eu2+. The electro-luminescence spectrum mainly distributes in blue (400–520 nm) and red (600–740 nm) regions and overlap with main absorption zone of plants. [Display omitted] • At the synthesis temperature of α-cordierite, Mg 2+ x Al 4-2 x Si 5+ x O 18 crystallized as β-cordierite (β-Mg 2+ x Al 4-2 x Si 5+ x O 18).. • A novel cyan-emitting β-Mg 2.25 Al 3·5 Si 5·25 O 18 :Eu2+ were synthesized. • The synthesized green phosphor is suitable for plant growth. [ABSTRACT FROM AUTHOR]

A series of SrSiAl2O3N2:Eu2+ (0.005 ≤x≤ 0.05) phosphors were successfully synthesized through a pressureless, facile, and efficient solid state route. The crystal structure, band structure, and their photoluminescence and cathodoluminescence properties were investigated in detail. The phosphors exhibit rod shape morphology with a uniform Eu2+ distribution. Under n-UV excitation the emission spectra shift from 477 to 497 nm with an increase of Eu2+ concentration. The concentration quenching mechanism of Eu2+ emission was dominated by the dipole–dipole interaction. The thermal stability is comparable to that of the commercial Ba2SiO4:Eu2+ phosphor. The phosphor also exhibits high current saturation and high resistance under low voltage electron bombardment. All the results indicate that the SrSiAl2O3N2:Eu2+ phosphors can be considered as candidates for application in both white LEDs and FEDs. [ABSTRACT FROM AUTHOR]