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The γ-Al2O3 and Ce3+ Cu2+-doped γ-Al2O3 powders have been synthesized by sol-gel method. Phases of the synthesized powders were characterized with X-ray diffraction. Morphological analysis and elemental composition of the samples were determined by scanning electron microscopy, high-resolution transmission electron microscopy and energy dispersive X-ray spectroscopy. Luminescence characterizations have been used to study the synthesized samples. Ab initio calculations by the use of local density approximation with the Hubbard U correlation were used to compute the structural, electronic and optical properties of γ-Al2O3 and Al2O3: Ce3+ Cu2+. The results indicate that the particle size and morphology of the samples depend on the concentration of the dopants. In comparison with undoped γ-Al2O3 sample, the intensities of emission peaks at 430 and 458 nm of Ce3+ Cu2+-doped γ-Al2O3 powders have been enhanced. This shows that, increasing Ce3+ and Cu2+ concentration causes an increase in the number of emitting ions which is expected in order to increase the number of applications ofγ-Al2O3: Ce3+ Cu2+ composite powders. The photoluminescence spectrum detected atλex= 253 nm shows a new peak located at 549 nm due to Cu2+ ions. This was confirmed computationally when the Ce_4f and Ce_5d states are found in the conduction band while the Cu_4p state was found at conduction band minimum and Cu_3d state at valence band maximum. This location of states showed there is no possible luminescence from the Ce3+ ions. The only possible luminescence was due to transition from Cu_4p to Cu_3d states.