Luminescence Properties of Green Phosphor Ca(2)Ga(2)(Ge(1-x)Si(x))O(7):y%Eu(2+) and Application

Rare earth luminescent materials demonstrate significant advantages in lighting and energy saving, and detection etc. In this paper, a series of Ca(2)Ga(2)(Ge(1-x)Si(x))O(7):y%Eu(2+) phosphors were synthesized by high-temperature solid-state reaction and characterized by X-ray diffraction and luminescence spectroscopy methods. The powder X-ray diffraction patterns reveal that all the phosphors are isostructural with a space group of P [Formula: see text] 21m. The excitation spectra of Ca(2)Ga(2)(Ge(1-x)Si(x))O(7):1%Eu(2+) phosphors exhibit significant overlapping of the host and the Eu(2+) absorption bands, which facilitates Eu(2+) absorbing the energy to increase its luminescence efficiency when excited by visible photons. The emission spectra show that the Eu(2+) doped phosphors have a broad emission band with a peak centered at 510 nm arising from the 4f(6)5d(1)→4f(7) transition. Variable temperature fluorescence reveals that the phosphor has a strong luminescence at low temperature but has a severe thermal quenching effect when temperature rises. The optimal Ca(2)Ga(2)(Ge(0.5)Si(0.5))O(7):1.0%Eu(2+) phosphor shows promise for application in the field of fingerprint identification based on the experimental results.