Microwave sol-gel synthesis, microstructural and spectroscopic properties of scheelite-type ternary molybdate upconversion phosphor NaPbLa(MoO4)3:Er3+/Yb3+

Abstract

New ternary molybdate NaPbLa(1-x-y)(MoO4)3:xEr 3+ ,yYb 3+ (x = y = 0, x = 0.05 and y = 0.35, 0.4, 0.45 and 0.5) phosphors were successfully fabricated by the MSG (microwave sol-gel) method, and the microstructural and spectroscopic properties were characterized. The crystal structure of NaPbLa(MoO4)3 (NPLM) was defined by Rietveld analysis in space group I41/a with unit cell parameters a = 5.3735(2) and c = 11.8668 (4) Å, V = 342.65(3) Å 3 , Z = 4 (RB = 6.64 %). The unit cell volume of NaPbLa(MoO4)3 (NPLM) was intermediate between those of NaLa(MoO4)2 and PbMoO4. Under the 980 nm excitation, upconverted yellowish-green emissions at transitions from 2 H11/2 and 4 S3/2 were observed. No concentration quenching in the subsystem of donor ions at the content up to 50 at.% and no cross-relaxation losses in the subsystem of acceptor ions at the concentrations as high as 5 at. % were verified. The individual chromaticity points for the NaPbLa(MoO4)3:Er 3+ ,Yb 3+ phosphors, corresponding to the equal-energy point in the standard CIE diagram, revealed yellowish-green emissions.

NUV light induced visible emission in Er3+‐activated NaSrLa(MoO4)O3 phosphors for green LEDs and thermometer

“…The X‐ray diffraction (XRD) patterns of NaSrLa(MoO 4 )O 3 : x Er 3+ ( x = 0.01, 0.02, 0.03, 0.04, 0.05, 0.06 and 0.07) phosphors are illustrated in Figure A. All the diffraction peaks of NaSrLa(MoO 4 )O 3 : x Er 3+ phosphors displayed similar results and these observed peaks were agreed well with previous results given by Lim et al Also, there were no diffraction peaks corresponding to the impurity phases or raw materials, indicating the formation of a pure crystalline phase in the crystal lattices. To further verify the purity of phase, the general structural analysis system was adopted to refine the typical Rietveld structure refinement of NaSrLa(MoO 4 )O 3 :0.04Er 3+ phosphor.…”

“…For example, Lim and co‐workers observed excellent luminescence properties in NaCaLa(MoO 4 )O 3 :Er 3+ ,Yb 3+ phosphors . A similar phenomenon was also observed in NaSrLa(MoO 4 )O 3 :Er 3+ ,Yb 3+ compounds …”

Structural Features of Y2O2SO4 via DFT Calculations of Electronic and Vibrational Properties

“…[1]. A large variety of rare-earth doped inorganic compounds have been synthesized, such as molybdates [2][3][4], tungstates [5][6][7], phosphates [8][9][10], aluminates [11][12][13] and silicates [14][15][16].…”

The role of the Tm3+ concentration on CaMoO4 properties processed by microwave hydrothermal under stirring condition

“…It allows improving the particles growth and nucleation rate and is recognized as an efficient method to control the size and morphology of the crystallites. [39][40][41][42] This methodology has several advantages, such as low-cost, short processing time, and low-energy consumption to manufacture ceramic powders. 43 Additionally, the hydrothermal synthesis, assisted by microwaves, favors the use of polar organic additives, such as polyethylene glycol (PEG), to improve the crystal growth and crystallization kinetics.…”