Luminescence properties of MgO: Fe3+ nanopowders for WLEDs under NUV excitation prepared via propellant combustion route

Abstract

Nanoparticles of Fe3+ doped (0–9 mol %) MgO were prepared using low temperature (400 °C) solution combustion technique using glycine as fuel. The powder X-ray diffraction (PXRD) patterns of the as-formed product exhibit cubic phase without further calcination. The effect of Fe3+ ions on luminescence properties of MgO was studied and results were discussed in detail. The phosphors exhibit strong red emission upon 378 nm (6A1(6S) → 4E(4G)) excitation. The characteristic photoluminescence (PL) peaks recorded at ∼513, 618 and 720 nm were attributed to transition of 4E + 4A1 (4G)→6A1 (6S), 4T2 (4G)→6A1 (6S), 4T1 (4G)→6A1 (6S) respectively. Further, the sample exhibit strong red emission at 720 nm, as a result the phosphor was useful for the applications for (NUV) excitation. The intensity of red emission was attributed to intrinsic defects, especially oxygen-vacancies, which could assist the energy transfer from the MgO host to the Fe3+ ions. The Commission International De I-Eclairage chromaticity co-ordinates were calculated from emission spectra and the values (x,y) were very close to National Television System Committee standard value of white emission. Therefore, the present phosphor was highly useful for display applications.

Keywords

• MgO: Fe3+
• Phosphor
• Photoluminescence
• CCT
• CIE Co-ordinates