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Aluminum oxide phosphors were synthesized by solution combustion method using urea and glycine as fuel. XRD results show that the sample synthesized with urea as a fuel is α-Al2O3 and glycine as a fuel is γ-Al2O3 with rhombohedral (R-3c) and cubic (Fd-3m) structures, respectively. The PL spectra of unirradiated and Ni7+ ions irradiated α-Al2O3 show a broad peak between 1.92 and 3.2 eV with maxima at 2.25 eV. This broad emission is assigned to the combination of F2 and F22+ centers. In addition, two sharp emissions observed at 1.83 eV (678 nm) and 1.78 eV (695) are due to R-lines of Mn4+ and Cr3+ respectively. The PL intensity is enhanced after Ni7+ ion irradiation in α-Al2O3 and the highest intensity is observed for 1 × 1012 Ni7+ cm−2. PL intensity decreases beyond this fluence. Unirradiated γ-Al2O3 samples have greater PL intensity, which decreases with Ni7+ ion irradiation. PL emissions of R-lines of Mn4+ and Cr3+ are missing in γ-Al2O3 due to a lower crystal field in the gamma phase.