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(Ca(1-x-y),Ln(y))MoO(4): xEu(3+) (Ln = Y, Gd) red phosphors were prepared by co-precipitation method with NH(4)HCO(3)-NH(3)center dot H(2)O system as the precipitating agent. X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), and energy-dispersive X-ray spectrometer (EDS) were used to characterize the structure and composition of the phosphors. The synthesized (Ca(1-x-y),Ln(y))MoO(4): xEu(3+) have scheelite structure with pure phase. FT-IR spectra show strong absorption peaks between 914 and 730 cm(-1) which are assigned to the vibration of O-Mo-O in MoO(4)(2-) tetrahedron. The EDS analysis reveals that the red phosphors have been successfully prepared by co-precipitation method according to theoretic ratio. Photoluminescence spectra show a red emission around 614 with 394 and 464 nm excitation, which is match well with the output wavelength of commercial ultraviolet and blue LED chips. The luminescent intensity of (Ca,Ln)MoO(4): Eu(3+) is obviously higher than that of CaMoO(4): xEu(3+). Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.