Photoluminescence studies of Eu3+ doped Y2O3 nanophosphor prepared by microwave hydrothermal method

Abstract

In this letter, the authors report the photoluminescence studies of Eu3+ doped Y2O3 nanorods, which have been synthesized by rapid microwave hydrothermal route within 6min. The nanostructured Eu3+ doped Y2O3 is characterized by x-ray diffraction, transmission electron microscopy, and photoluminescence. The emission spectrum shows transitions from the excited 5D0 state to FJ7 (J=0,1,2,3,4) levels of the Eu3+ ion. The most intense peak around 612nm is due to the D05→F27 transition, expected from the Judd-Ofelt selection rules [B. R. Judd, Phys. Rev. 127, 750 (1962); G. S. Ofelt, J. Chem. Phys. 37, 511 (1962)]. Photoluminescence measurements demonstrated that the nanocrystalline Eu3+:Y2O3 phase shows higher photoluminescence intensity.

Microwave assisted synthesis of monodispersed Y2O3 and Y2O3:Eu3+ particles

“…A wide range of synthesis techniques have been developed for the preparation of pure and doped nanocrystalline Y 2 O 3 phosphors with different morphologies, including precipitation method [17], sol-gel route [18], combustion synthesis [19], hydrothermal process [20], spray pyrolysis method [21], microemulsion method [22], chemical vapour deposition (CVD) technique [23], and microwave assisted synthesis methods [24][25][26][27]. Among them, microwave assisted heating systems distinguished as quick, reproducible, simple, and energy efficient method with very short reaction times and higher yield of products.…”

Comparison of Microwave Assisted Solvothermal and Hydrothermal Syntheses of LiFePO4/C Nanocomposite Cathodes for Lithium Ion Batteries

“…We present here a novel microwave-assisted hydrothermal (employing water as a solvent) and solvothermal (employing tetraethyleneglycol as a solvent) synthesis approach that offers highly crystalline LiFePO 4 with a controlled, smaller particle size within a short reaction time (5−15 min) at <300 °C. The methods take advantage of both the microwave irradiation and the solvothermal or hydrothermal effect to offer products with controlled particle size within a short reaction time. − We also present an in situ coating of a thin layer of carbon on nanostructured LiFePO 4 by a carbonization of glucose during the hydrothermal process (one pot synthesis) followed by annealing at 700 °C for 1 h in 2% H 2 /98% Ar in order to improve the structural order of the carbon coating as well as an ex situ coating of carbon by heating the nanostructured LiFePO 4 obtained by the microwave-solvothermal method with sucrose in 2% H 2 /98% Ar at 700 °C for 1 h. The obtained LiFePO 4 /C nanocomposites with a typical nanocrystalline LiFePO 4 core and a carbon shell (“core-shell”) exhibit excellent electrochemical performance with respect to lithium-storage capacity, cycling performance, and rate capability.…”

Optimized photoluminescence of red phosphor Na2SnF6:Mn4+ as red phosphor in the application in “warm” white LEDs

“…Conventional red phosphors with Eu 3+ doping have weak absorption in blue region because of the inner 4 f forbidden transitions of Eu 3+ which limits their applications in solid‐state lighting . Mn 4+ ions with 3 d 3 electronic configuration possess a group of sharp emission peaks in red region and a broad band excitation with a maximum in blue region, which makes Mn 4+ ions doped red phosphors play as alternative candidates for compensating red components for WLEDs .…”

“…Conventional red phosphors with Eu 3+ doping have weak absorption in blue region because of the inner 4f forbidden transitions of Eu 3+ which limits their applications in solid-state lighting. 6,7 Mn 4+ ions with 3d 3 electronic configuration possess a group of sharp emission peaks in red region and a broad band excitation with a maximum in blue region, which makes Mn 4+ ions doped red phosphors play as alternative candidates for compensating red components for WLEDs. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] Mn 4+ -doped alkaline aluminates show promise in WLEDs but repeated sintering processes at high temperature (>1200°C) are needed for synthesis of these phosphors.…”