X-ray analysis and optical studies of Dy3+ doped NaSrB5O9 microstructures for white light generation

作者：Dillip G R; Ramesh B; Reddy C Madhukar; Mallikarjuna K; Ravi O; Dhoble S J; Joo S W; Raju B Deva Prasad^*

来源：Journal of Alloys and Compounds, 2014, 615: 719-727.

DOI：10.1016/j.jallcom.2014.07.017

• Phosphor
• Strain analysis
• Microstructure
• Luminescence

A white light emitting phosphor NaSrB5O9:Dy3+ was synthesized by a conventional solid state reaction method. The structure of the phosphors was analyzed by powder X-ray diffraction (XRD), revealing that the phosphors crystallized in monoclinic crystal structure with the space group (P2(1)/c). Williamson-Hall (W-H) analysis was used to study the individual contributions of crystallite sizes and lattice strain on the peak broadening of NaSrB5O9:Dy3+ phosphors. Monoclinic microstructures of nearly plate-like morphologies were observed in the FE-SEM images. Upon near-UV excitation wavelength (390 nm), the blue emission at similar to 482 nm (H-6(15/2)) and yellow emission at similar to 584 nm (H-6(13/2)) were observed in the phosphors. The critical quenching concentration of Dy3+ in NaSrB5O9 phosphor was found to be 3 at.% with the critical distance (R-c) of similar to 22.30 angstrom and the corresponding concentration quenching mechanism was testified to be the exchange interaction between the dopant Dy3+ ions. In order to investigate the application in white LEDs, the Commission International de l%26apos;Eclairage (CIE) chromaticity coordinates, color temperature and decay curve measurements of Dy3+ ions doped NaSrB5O9 phosphors were carried out. The yellow to blue (Y/B) emission integrated intensity ratio is maximum (similar to 0.9) for all the concentrations, suggesting that the phosphors favor for white illumination.

• 出版日期2014-12-5