Preparation and characterization of nanosized ZnGa2-xCrxO4 phosphors

Cr-doped zinc gallate phosphors were prepared via citric gel route and their luminous properties were characterized by photoluminescence in this study. From the results of XRD studies, it was found that spinel phase formed exclusively in the ZnGa_2-xCr_xO₄ phosphors (O ≤ x ≤ 0.010) prepared by heat-treatment at 700°C for 5 hours and the lattice constant increased linearly from 8.36 to 8.38 Å with the amount of Cr³⁺-doping. The photoluminescence studies manifested that the absorbance at wavelengths of 437 and 580 nm. All of the prepared phosphors exhibit the characteristic emission peaks at wavelengths of 669, 680, 688, 694, 708, and 713 nm independent of the amount of Cr³⁺-doping as they were excited with lights of wavelengths of 437 and 580 nm.