Photoluminescence characterisation of Zn1–xCdxAl2O4:Eu nanophosphor for solid state lighting

Abstract

All the phosphor are prepared as Zn1-x-yCdxAl2O4:Euy by combustion method. The formation of crystalline aluminates was confirmed by X-ray diffraction. The prepared phosphor was characterised by SEM, EDS, particle size analyser and photoluminescence (PL) techniques. The PL emission spectra of Zn1-x-yCdxAl2O4:Euy phosphor shows prominent peaks at 613 nm and 580 nm (excited by 394 nm wavelengths). It is also observed that the Eu ions are incorporated in trivalent form. The Eu ion concentration is kept constant at 0.5 mol% and Cd concentration varies from 0.1 mol% to 1 mol% in the host lattice. The increase in concentration of Cd ions increases the PL emission intensity. So it is clear that the replacement of Zn ion into Cd ions increased the crystallinity, hence, increases the PL intensity. The SEM and particle size analyser results indicate that the prepared phosphor are in nanosize and increase in concentration of Cd ions increases the particle size of phosphor.