PLANT MEDIATED COMBUSTION SYNTHESIS OF Tb3+ DOPED STRONTIUM ALUMINATE NANOPHOSPHOR FOR DISPLAY DEVICE APPLICATIONS.

M.Chitra; R.Ananda Kumari; H.Nagabhushana

Volume : VIII, Issue : VII, July - 2018

PLANT MEDIATED COMBUSTION SYNTHESIS OF Tb3+ DOPED STRONTIUM ALUMINATE NANOPHOSPHOR FOR DISPLAY DEVICE APPLICATIONS.

M. Chitra, R. Ananda Kumari, H. Nagabhushana

Abstract :

For the first time pure and Tb³⁺ (1–7mol%) doped SrAl₂O₄nanophosphors were synthesized via solution combustion method by using the Calotropisgigantea plant milk as fuel. The prepared samples were calcined at 800 ºCfor 3 hours, the final product was well characterized.The powder X–ray diffraction (PXRD) profiles of nanophosphors showed crystalline monoclinic phase. The effect of concentration of bio–fuel play a vital role in tuning the morphologies of SrAl₂O₄.The samples show the pores and voids on the surface that formed by the escaping gases during the combustion method. The morphology of the powders reflects the inherent nature of the combustion process. The images show non uniform and irregular shapes of the particles. The particle sizes were further confirmed by Transmission electron microscope (TEM) and were found to be in the range of ––– nm. The energy band gaps for the prepared samples estimated using DRS weres found to be in the range 5.81–6.11 eV. Fourier transform infrared spectral studies were also carried out to evaluate the stretching and viational bands in the product. Photoluminescence (PL) studies were carried out for SrAl₂O₄: Tb³⁺ (1–7 mol %) nanophosphorsunder 376 nm excitation wavelength. The strongest emission peak is located 516 nm and was attributed to ⁵D_{4 →}⁷F₅transition ,while the other peaks at ~486 nm,~541 nm corresponds to the transitions ⁵D_4→⁷F₆, ⁵D_4→⁷F₅ respectively. Further CIE and CCT were estimated and found that the color co–ordinates fall in the green color region. The overall results together indicate that the prepared nanophosphors were highly useful in display device applications.