Article

Color point tuning of Y3Al5O12:Ce3+ phosphor Via Mn2+-Si4+ incorporation for white light generation

Journal of Materials Chemistry (Impact Factor: 7.44). 07/2012; DOI: 10.1039/C2JM32233A

ABSTRACT In this paper, the color point tuning of Y3Al5O12:Ce3+ phosphor has been realized by the incorporation of Mn2+-Si4+. The Mn2+ ions occupy the dodecahedral crystallographic Y3+ site, while the Si4+ ions substitute the tetrahedral Al3+ crystallographic site in the obtained powder. Under the 450 nm excitation, the YAG:Ce3+, Mn2+, Si4+ samples exhibit the typical yellowish-green emission band of the Ce3+ ions, as well as an orange emission band of the Mn2+ ions. Furthermore, the intensity ratio of the orange/yellowish-green band can be enhanced through the increase of Mn2+-Si4+ content. The intense orange emission band of the Mn2+ ions is attributed to the effective energy transfer from the Ce3+ to Mn2+ ions, which has been justified through the luminescence spectra and the fluorescence decay dynamics. The related mechanism was demonstrated to be the electric dipole-quadrupole interaction based on the Inokuti-Hirayama theoretical model, and critical distance is calculated to be 8.57A by the spectral overla

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