Luminescence and spectroscopic investigations on Gd3+ doped ZnO nanophosphor

The present paper describes the synthesis of 0.1 mol% Gadolinium (Gd) doped Zinc oxide (ZnO) nanophosphor by solution combustion method using Oxalyl dihydrazide (ODH) fuel. Powder X-ray diffraction (PXRD) peaks are well matched with the standard hexagonal wurtzite structure of ZnO (JCPDS card no. 36-1451). SEM and TEM analysis reveals porous morphology of as -formed sample with particles having narrow size distribution in the range ∼60-70 nm, in good agreement with XRD data. The PL spectrum of Gd doped ZnO sample exhibits an extra blue emission at 441 nm (∼2.81 eV) in addition to the emission bands from undoped ZnO. From the TL data of ZnO:Gd nanophosphor with UV irradiation, it is observed that considerable amount of re-trapping is taking place in all the TL second order peaks. The EPR spectrum exhibits a number of resonance signals suggesting that Gd3+ ions are experiencing different crystal field strength and Zeeman interactions.