Luminescence Properties of Fine-Grained ScVO4:Eu3+ and Sc0.93-xLnxVO4:Eu0.073+ (Ln = Y,La,Gd,Lu) Phosphors

ScVO4:Eu3+ and Sc(0.93-x)Ln(x)VO(4):Eu-0.07(3+) (Ln = Y,La,Gd,Lu) phosphors were prepared by a solid-state reaction method. The luminescence properties, crystal structures and surface morphologies of as-prepared phosphors were systematically investigated. A strong band between 200-400 nm in the excitation spectrum and a region of red emission are observed. The optimum concentration of Eu3+ activator is found to be 7 mol% in ScVO4 host. The PL intensities can be improved to a great extent via doping with Ln(3+) (content x), which reach the maximum values of 156%, 120%, 120%, and 133% relative to Sc0.93VO4:Eu-0.07(3+) at x = 0.20 for Y and La and x = 0.05 for Gd and Lu, respectively. Meanwhile, the phosphors show high quantum efficiencies and low thermal quenching. The XRD results indicate the successful formation a Zircon-type structure of ScVO4:Eu3+ and Sc(0.93-x)Ln(x)VO(4):Eu-0.07(3+) samples. Through the calculation of lattice parameters, the peak shifts in the excitation spectra from 330.0 nm(Sc) to 330.4 nm(Lu), 330.8 nm(Y), 331.4 nm(Gd) and 336.6 nm(La) are ascribed to the expansion of unit-cell volumes. The SEM images and particle size distributions show that the samples consist of well-crystallized particles with uniform morphology, small particle size and narrow size distribution, which are desirable for high performance of phosphor. (C) 2014 The Electrochemical Society. All rights reserved.