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In this paper, the color point tuning of Y 3 Al 5 O 12 : Ce 3+ phosphor has been realized by the incorporation of Mn 2+ -Si 4+ . The Mn 2+ ions occupy the dodecahedral crystallographic Y 3+ site, while the Si 4+ ions substitute the tetrahedral Al 3+ crystallographic site in the obtained powder. Under 450 nm excitation, the YAG : Ce 3+ ,Mn 2+ ,Si 4+ samples exhibit the typical yellowish-green emission band of the Ce 3+ ions, as well as an orange emission band of the Mn 2+ ions. Furthermore, the intensity ratio of the orange/yellowish-green band can be enhanced through the increase of Mn 2+ -Si 4+ content. The intense orange emission band of the Mn 2+ ions is attributed to the effective energy transfer from the Ce 3+ to Mn 2+ 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 8.6A by the spectral overlap method.

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In this study, we successfully prepare SnO(2) nanoparticles inside the pore channels of CMK-3 ordered mesoporous carbon via sonochemical method. The content of SnO(2) is 17 wt % calculated according to the energy-dispersive X-ray spectroscopy (EDS) result. CMK-3 with 17 wt % loading of SnO(2) nanoparticles has a large specific surface area and pore volume. Electrochemical performance demonstrates that the ordered SnO(2)/CMK-3 nanocomposites electrode possesses higher reversible capacity and cycling stability than that of original CMK-3 electrode. Moreover, the ordered SnO(2)/CMK-3 nanocomposites electrode also exhibits high capacity at higher charge/discharge rate. The improved electrochemical performance is attributed to the nanometer-sized SnO(2) formed inside CMK-3 and the large surface area of the mesopores (3.4 nm) in which the SnO(2) nanoparticles are formed.

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A series of single-component Sr 3 Lu(PO 4 ) 3 :Eu 2+ ,Mn 2+ phosphors were successfully synthesized by solid-state reaction, and their photoluminescence properties were investigated. The Sr 3 Lu(PO 4 ) 3 :Eu 2+ ,Mn 2+ phosphor system was efficiently excited at wavelength ranging from 250 to 420 nm, which is well-matched with ultraviolet (UV) light-emitting diode (LED) chips. As a result of fine-tuning of the emission composition of the Eu 2+ and Mn 2+ ions, warm white light emission can be realized by combining the emission of Eu 2+ and Mn 2+ in a single host lattice under UV light excitation. Efficient resonant energy transfer from the Eu 2+ to Mn 2+ ions was demonstrated to be a dipoleÀquadrupole mechanism in such system, and the energy transfer efficiency increases with an increase in the Mn 2+ doping content, which was confirmed by the luminescence spectra and fluorescence decay curves. In addition, the energy transfer efficiency and critical distance were also calculated. The results indicate that the developed phosphor can be used as a potential white-light-emitting phosphor for white LEDs.