Development of luminescent materials with strong UV-blue absorption

A new green emitting phosphor Eu-activated orthoaluminate has been prepared by low temperature combustion synthesis of Eu-nitrate, Al-nitrate and a fuel (hydrazine). The crystalline structure was identified by X-ray diffraction and all the peaks could be indexed to the orthorhombic AlEuO3 having a perovskite-type structure. A strong green-yellowish photholuminescence peak, centered at around 538 nm, was registered at room temperature when the phosphor was excited by ultraviolet photons in the range of λ = 250-450 nm due to electronic transitions generated in Eu2+. This wide excitation range makes AlEuO3:Eu2+ suitable for applications in solid state light devices, particularly at long UV wavelengths. Cathodoluminescent properties for the same phosphor powder were analyzed and produced a strong red peak centered at λ = 616 nm, which is typical of the hypersensitive 5D0 → 7F2 transitions in Eu3+.