Synthesis, Characterization and Luminescent Properties of La2Zr2O7:Eu3+ Nanorods

Abstract

The Eu3+-doped La2Zr2O7phosphor with rod-like morphology was successfully synthesized by conventional solid state reaction and hydrothermal method. X-ray diffraction patterns, transmission electron microscopy, and photoluminescence spectra were employed to characterize its structure and morphology as well as luminescent properties. The results indicated that the red-emitting phosphor La2Zr2O7:Eu3+ had well crystallized and belonged to the cubic structure with space group of Fd3m. The as-obtained product mainly appeared as straight nanorods with an average diameter of 47 nm and length of 50–700 nm. The possible growth mechanism was also discussed. It was found that under blue excitation with a wavelength of 466 nm, the La2Zr2O7:Eu3+ phosphor exhibited a characteristic red emission at 616 nm that was attributed to the hypersensitive D50→7F2electric dipole transition of Eu3+ ions. Meanwhile, it was more interesting to note that the emission of D51→7FJ (J=0, 1, 2) transitions and the splitting patterns of 5D0→7FJ (J=1, 2, 4) transitions of Eu3+ ions can be observed in the luminescent spectra of La2Zr2O7:Eu3+. It was demonstrated that Eu3+ preferred to occupy a low symmetry site.

Particle Size and Crystal Phase Dependent Photoluminescence of La2Zr2O7:Eu3+ Nanoparticles

“…Primarily, hosts with A 2 B 2 O 7 composition have been investigated for many applications including nuclear waste host materials, high‐temperature heating elements, thermal barrier layers, oxidation catalysts and scintillator materials in x‐ray computed tomographic detectors, and so on . As RE elements in A 2 B 2 O 7 can easily be replaced by other RE ions, they are now considered as promising luminescent host materials . However, research on A 2 B 2 O 7 as a luminescence host, especially the role of particle size and crystal structure on luminescence properties, is on the preliminary stage, which is primarily due to the lack of a facile synthetic method to effectively control of its crystal size and phase.…”

Systematic Studies on RE2Hf2O7:5%Eu3+ (RE = Y, La, Pr, Gd, Er, and Lu) Nanoparticles: Effects of the A-Site RE3+ Cation and Calcination on Structure and Photoluminescence

“…According to theoretical 4 studies, Eu 3+ -doped RE 2 Hf 2 O 7 has a valence band largely consisting of bonding O 2-2p and RE 3+ 6s orbitals and a conduction band largely consisting of Hf 4+ 5d, antibonding O 2-2p, and RE 3+ 6p orbitals. 13,18 Eu 3+ emits red under UV excitation through a charge transfer band (CTB), followed by energy transfer to Eu 3+ .…”

“…[1][2][3][4] Recently there has been a great amount of interest in the derivative structures, such as A 2 B 2 O 7 , of dioxide BO 2 (e.g. B = Zr, Ce, and Hf) type compounds as RE host materials due to their binary metal cation sites, where the larger A site cation can be replaced with trivalent RE ions and B is a smaller transition metal cation.…”

“…4,7,[26][27] The solid-state synthesis method usually requires high temperatures above 1000 °C where it is difficult to control the morphology and crystal phase of the particles. In comparison, the synthesis of binary oxides in the molten salt method is more attractive than many other solid-state methods, due to the homogenous nanosized morphology of products and lower synthesis temperatures.…”

Optical and X-ray induced luminescence from Eu3+ doped La2Zr2O7 nanoparticles

“…Eu 3+ is one of the most studied rare earth ions because of its unique Stokes emission characteristics [2,3,24,[36][37][38][39][40][41][42][43][44]. In addition, it has a nearly monochromatic strong visible red emission around 612 nm.…”