The solution combustion method is used to synthesize nanocrystalline (Y0.5Gd0.5)PO4:Eu-0.06 phosphor powders. The crystal structure and photoluminescence properties of (Y0.5Gd0.5)PO4:Eu-0.06 phosphors are significantly influenced by the calcination temperature. The amount of the tetragonal xenotime structure increases with an increase of the calcination temperature. The higher calcination temperature yields the higher value of (D-5(0)-> F-7(2))/(D-5(0)-> F-7(1)), improving the color purity, which originates from the phase transformation from the monoclinic monazite structure to the tetragonal xenotime structure. The (Y0.5Gd0.5)PO4:Eu-0.06 phosphor calcined at 1300 degrees C emits the purest red color. We need to obtain the tetragonal xenotime structure for improved red color purity. (C) 2013 Elsevier B.V. All rights reserved.