Synthesis and photoluminescence properties of Ca sub(3)R sub(2-x)WO sub(9):xEu super(3+) (R = Y, Gd) phosphors

• Published in: Journal of rare earths Vol. 33; no. 2; pp. 135 - 139
• Main Authors: RU, Jingjing, QIN, Xiaohuan, VAN, Guiyang, CHEN, Jianzhong
• Format: Journal Article
• Language: English
• Published: 01-02-2015
• Subjects: Diffraction; Field emission; Fourier transforms; Infrared spectroscopy; Optimization; Phosphors; Photoluminescence; Rare earth metals; Sintering
• ISSN: 1002-0721
• DOI: 10.1016/S1002-0721(14)60393-8

Ca sub(3)R sub(2-x) WO sub(9):xEu super(3+) (R = Y, Gd) red-emitting phosphors were prepared by solid state reactions. These samples were characterized by differential scanning calorimetry and thermogravimetry analysis (DSC-TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and field emission scanning electron microscopy (FE-SEM) analyses. The optimum sintering temperature for these phosphors was 1100 [degrees]C, and the optimum sintering time was 2 h. The optimum doped concentration of Eu super(3+) in Ca sub(3)Y sub(2-x)WO sub(9):xEu super(3+) and Ca sub(2) Gd sub(2-x)WO sub(9):xEu super(3) were x = 1.5 and x = 1.1, respectively. These phosphors could be excited by near-UV light of 394 nm and blue light of 465 nm, and showed strong red emission line at 612 nm ( super(5)D sub(0) arrow right super(7)F sub(2)), which indicated that Ca sub(3)R sub(2-x)WO sub(9):xEu super(3+) (R = Y, Gd) were promising red candidates for white LED.