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Abstract: SrAl2O4:Eu phosphors with various doping concentrations were synthesized via a urea assisted solution-combustion method in a reducing atmosphere without any post-annealing process. The phosphors were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (SEM), photoluminescence (PL), X-ray excited luminescence (XEL), and X-ray photoelectron spectroscopy (XPS). The XRD results show that the samples exhibit a monoclinic phase in crystal structure. The PL measurements show that the intensity of luminescence emission from divalent Eu2+ ions is increased with increasing europium concentration up to a maximum of 2.5mol%, then decreases at higher concentration due to the concentration quenching effect. The emission from trivalent Eu3+ ions occurs when the doping concentration is higher than 12.5mol%. The XPS measurements also confirm the trends of Eu2+ and Eu3+ with changes in concentration. The results indicate that the luminescence color components of the phosphors can be adjusted by the doping concentration; this is a very important result for practical applications. [Copyright &y& Elsevier]