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Low temperature solution combustion method using urea as fuel was employed for the synthesis of α-Al 2 O 3 :Eu 3+ nanophosphor. The synthesized nanophosphor was well characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and diffused reflectance spectroscopy. XRD results reveal that Eu 3+ doped sample corresponds to the alpha phase of Al 2 O 3 . TEM analysis reveals particle size distribution in the range of 7–33 nm. XPS results reveal that no impurity elements was present in the nanophosphor and chemical state of the Eu was “+3” in nanophosphor, which favors the substitution of Eu ion in the Al 2 O 3 host matrix. A bandgap of 5.97 eV is calculated using diffused reflectance spectrum. PL spectrum showed that under UV excitations (228, 396 nm) α-Al 2 O 3 :Eu 3+ nanophosphor exhibits strong red emission due to characteristic 4 f –4 f transitions of Eu 3+ ( 5 D 0 → 7 F j ; j = 1, 2, 3, 4). The strong emission peak at 616 nm under 228 nm excitation may be used for possible practical applications in gamma and X-ray scintillators. |
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