Nanoparticle doped YbxMg1-xAl2O4 (where x = 0.00, 0.05 and 0.01) synthesized through igniting a stoichiometric mixture
of aluminum, magnesium and ytterbium nitrates with malonic acid dihydrazide as a solid fuel, followed by annealing at
800, 1000 and 1200 oC. The obtained samples were characterized by different tools as thermal analysis, X-ray diffractions,
UV-Vis spectroscopy, transmission electron microscopy and infrared spectroscopy. Crystalline particle sizes were calculated
from X-ray diffraction for Yb0.1Mg0.9Al2O4, Yb0.05Mg0.95Al2O4 and MgAl2O4 with a size of 12.3, 11.3 and 10.5 nm
respectively, at1000 oC in the same condition. Thermal analysis gives us that the crystalline phase of MgAl2O4 and doping
materials are formed after annealing after 700 oC which agree with X-ray diffraction. TEM micrograph shows sheet and
spherical shapes for Yb0.1Mg0.9Al2O4 and MgAl2O4 samples which are annealing at 1000 °C. The edges of bands were
shifted to higher wavelength and band energies shifted to lower values as result of increasing the amount of Yb3+ in the
lattice of MgAl2O4 and calcinations temperatures.