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We successfully synthesized Sr3Gd2(BO3)4:Eu3+ (SGBO:Eu3+) and Sr3Y2(BO3)4:Eu3+ (SYBO:Eu3+) phosphors through a high-temperature solid-state reaction. The structure was shown by x-ray powder diffraction and the irregular morphology of SGBO:Eu3+ and SYBO:Eu3+ phosphors was seen by a field emission scanning electron microscope. Additionally, the photoluminescence excitation spectra and emission spectra were also presented. As shown in the results, the phosphors could be stimulated by near ultraviolet light and then exhibited red light emission, which is consistent with the calculated color coordinates. The quenching concentrations of Eu3+ in SYBO and SGBO hosts are much higher than that in other borate hosts. In particular, far-red light-emitting at 702 nm due to the transition of 5D0 → 7F4 is beneficial to plant growth. The results show that the prepared samples have application value in white light emitting diodes.

Far red-emitting Mn4+ activated oxide phosphors based on the substitution of Mn4+ for Sb5+ in the lattice of Sr3LiSbO6 (SLSO) was prepared via solid state reaction process. The phases and micrographs of powders were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The luminescent properties of the samples with varying Mn4+ concentrations were investigated, and the result indicates that prepared phosphor SLSO:Mn4+ can be excited by (UV) light and exhibit intense far red emission at 698 nm. This emission band is well matched with the absorption band of phytochrome PFR. The mechanism of quenching concentration has been investigated. The thermal stability and thermal quenching concentration of SLSO:Mn4+ were discussed. In addition, the internal quantum efficiency (IQE) has been tested and calculated. All the above results suggest that the SLSO:Mn4+ phosphors have great potential applications in plant growth n-UV LEDs.

ALa9(SiO4)6O2: Eu3+ (A = Li, Na) oxyapatite phosphors have been synthesized via traditional solid-state methods X-ray powder diffraction (XRD) analysis confirmed the phase formation of ALa9(SiO4)6O2: Eu3+ (A = Li, Na) materials. The scanning electron microscope (SEM) image exhibited the irregular morphology of ALa9(SiO4)6O2: Eu3+ (A = Li, Na) particles. The photoluminescence excitation (PLE) and emission (PL) spectra were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light, and it exhibited red light emission. The calculated color coordinates lies in the red region. All the obtained results suggest that the prepared phosphors exhibit great potential application as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor Ca 9 Na 0.667 Gd(PO 4 ) 7 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of Ca 9 Na 0.667 Gd(PO 4 ) 7 :Eu 3+ materials. The photoluminescence excitation (PLE) and emission (PL) spectra were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The calculated color coordinates lies in the red region. All the obtained results suggest that the prepared phosphors exhibit great potential application as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor LiY 9 (SiO 4 ) 6 O 2 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of LiY 9 (SiO 4 ) 6 O 2 :Eu 3+ materials. The photoluminescence excitation and emission spectra, and the concentration dependence of the emission intensity of the phosphor were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The calculated color coordinates lies in the red region. Therefore, these obtained results suggest that the prepared phosphors exhibit great potential for use as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs).

A novel red-emitting phosphor La 0.67 Mg 0.5 W 0.5 O 3 :Eu 3+ has been synthesized by a high-temperature solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of La 0.67 Mg 0.5 W 0.5 O 3 :Eu 3+ materials. The photoluminescence excitation and emission spectra, the concentration dependence of the emission intensity, and decay curves of the phosphor were investigated. The results showed that the phosphor could be efficiently excited by the near ultraviolet (NUV) light and blue light, and it exhibited red light emission. The decay time was also determined for various concentrations of Eu 3+ in La 0.67 Mg 0.5 W 0.5 O 3 . The calculated color coordinates lies in the red region. Therefore, these obtained results suggest that the prepared phosphors exhibit great potential for use as red emitting phosphor for near ultraviolet white light emitting diodes (NUV WLEDs)