Luminescent properties of Eu3+, Tb3+ or Bi3+ activated yttrium germanates

Abstract Preliminary studies were conducted on Eu 3+ , Tb 3+ or Bi 3+ doped Y 2 Ge 2 O 7 , Y 2 GeO 5 and Y 4 GeO 8 phosphors. Both photoluminescence and cathodoluminescent properties of the materials were measured. Among these materials, the luminescent intensities of Y 2 Ge 2 O 7 :Eu, Y 2 GeO 5 :Tb and Y 2 Ge 2 O 7 :Bi are relatively high and the luminescent colors of them are red, green and blue, respectively. In order to improve the luminescent properties for field emission display applications, further optimization is necessary. In addition, X-ray powder diffraction results indicate that Y 4 GeO 8 phase forms in an orthorhombic unit cell, the parameters of which are: a =1.4976(5) nm, b =0.9357(6) nm, c =0.5885(3) nm, V cell =0.82467(2) nm 3 .