The sulfate ions modified YAG∶Ce3+ phosphors were prepared by co-precipitation method and characterized by X-ray diffraction,transmission electron microscopy,and photoluminescence.Effects of sulfate ions on the photoluminescence (PL) property of the as-prepared YAG∶Ce3+ phosphors were studied,with sodium dodecyl sulfate (SDS) being added to R3+ (Ce3+,y3+,Al3+) ions.Resuits indicated that pure YAG∶Ce3+ phosphors with different ratios of sulfate ions could be easily obtained by calcining the as-synthesized precursor at 950 ℃ for 2 h,the YAG∶Ce3+ phosphors with an optimal mass ratio of 3.5 wt.％ SDS had the highest emission intensity and the best dispersion behavior,and the fluorescence decay of the as-obtained YAG∶Ce3+ phosphors was related to the lattice defect,reabsorption and cross correlation.Furthermore,thermal quenching properties of the YAG∶Ce3+ phosphors and the YAG∶Ce3+ phosphors with 3.5 wt.％SDS were also discussed,indicating that the YAG∶Ce3+ with SDS phosphors could have potential applications in the daylight LEDs or warm white LEDs.