Spectroscopic properties of Eu3+:KLa(WO4)2 novel red phosphors

Eu3+:KLa(WO4)2 (Eu:KLW) phosphors were prepared through Pechini type sol-gel method. Low temperature synthesis was achieved through polyesterification between citric acid and ethylene glycol during the growth procedure. The properties of phosphors were analysed using X-ray diffractogram (XRD), scanning electron microscopy (SEM), Raman and luminescence spectroscopy. An effective energy transfer from the tungstate matrix to the activator Eu3+ was observed. Intense red emission in Eu:KLW phosphors was observed while excited with f-f transitions of Eu3+. The Judd-Ofelt (J-O) intensity parameters Ω2 and Ω4 were obtained from the emission intensities of 5D0→7F2,4, respectively by taking the magnetic dipole 5D0→7F1 emission band intensity as reference. The CIE colour co-ordinates of the Eu:KLW red phosphors was calculated (x=0.650, y=0.348), which are close to NTSC standard values.