Luminescent Properties of Pure Cubic Phase Y₂O₃/Eu³⁺ Nanotubes/Nanowires Prepared by a Hydrothermal Method

Abstract

One-dimensional pure cubic Y(2)O(3)/Eu(3+) nanocrystals (NCs) were synthesized by a hydrothermal method at various temperatures. The NCs prepared at 130 degrees C yielded nanotubes (NTs) with wall thickness of 5-10 nm and outer diameter of 20-40 nm. The NCs prepared at 170 and 180 degrees C yielded nanowires (NWs) with diameters of approximately 100 and approximately 300 nm, respectively. Their luminescent properties, including electronic transition processes, local environments surrounding Eu(3+) ions, electron-phonon coupling, and UV light irradiation induced spectral changes have been systematically studied and compared. The results indicate that the Y(2)O(3)/Eu(3+) NTs and NWs have strong red (5)D(0)-(7)F(2) transitions. The fluorescence lifetime of (5)D(1)-(7)F(1) hardly changes in different samples, while that of (5)D(0)-(7)F(2) decreases a small amount in Y(2)O(3)/Eu(3+) NTs. The (5)D(0)-(7)F(2) lines originate from the emissions of Eu(3+) ions occupying one C(2) site, like that in the bulk powders. The phonon sideline with a frequency shift of 40-50 cm(-1) appears at the low-energy side of the (7)F(0)-(5)D(0) zero phonon line. The relative intensity of the sideline to zero phonon line increases by varying from NTs to NWs, and the spectral position of the phonon sideline shifts red. The UV light irradiation induced spectral change in the charge-transfer band was studied. The results indicate that the spectral change is dependent on sample size and is wavelength selective. A detailed model was proposed to explain the light-induced spectral change.

Controlling the morphology of yttrium oxide through different precursors synthesized by hydrothermal method

“…This morphology is familiar for hexagonal Y(OH) 3 . Many researches [8][9][10][11]17] have previously reported the synthesis of Y(OH) 3 and corresponding Y 2 O 3 nanotubes under strong basic conditions using NaOH or KOH as base. We supposed that similar structures could be prepared in ammonia solution as long as high pH value was achieved.…”

“…Industrially, yttrium oxide is produced by solid state decomposition reaction at high temperatures. Gas-phase condensation [1], precipitation [2], sol-gel processing [3], combustion [4], pyrolysis [5], and recently, hydrothermal synthesis [6][7][8][9][10][11][12][13][14][15][16][17] are other physical and chemical techniques for preparation of yttrium oxide include Hydrothermal synthesis is widely accepted as a simple and mild method to prepare high crystalline materials with controlled particle size. Recently, the hydrothermal synthesis of yttrium oxide attracted increasing attention owing to the prospects of producing high-quality, welldispersed crystals as well as the convenience in preparing homogeneous doped materials.…”

“…For example, the reported sizes of yttrium oxide range from several nanometers to tens of micrometers, and various shapes like spherical particle [6,15], rod or wire [6][7][16][17], tube [8-11, 15, 17], belt [7,13], trilobal prism [14], and plate [6,[15][16] were described. All of these bewildering results trigger a critical demand for a comprehensive investigation on hydrothermal synthesis of yttrium-based compounds.…”

Characterization and photoluminescence properties of aluminum borate nanorods doped with Eu

“…7,[14][15][16][17] In our previous work, we synthesized aluminum borate nanowires ͑Al 18 B 4 O 33 ͒ in a large yield. 18,19 Aluminum borate possesses a high melting point and is stable in oxidizing environment.…”

Synthesis by organic molten salt method and characterization of chalcopyrite AgInS2 nanorods

“…[1][2][3]. Compared to their bulk counterparts, nanomaterials are expected to possess novel physical properties resulting from the quantum effects and a high surface-to-volume ratio [4][5][6][7]. Nanometer-sized inorganic low dimensional systems exhibit a wide range of optical and electric properties [8], which rely sensitively on both size and morphology [9,10].…”