The compound Ca2GdSbO6 with a stable double perovskite structure is one of the high-quality materials used as a phosphor matrix.A new series of reddish-orange phosphors Ca2Gd1-xSbO6∶xSm3+(x=0、0.01、0.02、0.03、0.04、0.05、0.06)were synthesized by high-temperature solid-state method.The phase composition,optical properties,crystal structure and chemical purity of the prepared phos-phors were characterized via X-ray diffractometer(XRD),scanning electron microscope(SEM),photolu-minescence spectroscope(PL),high-temperature fluorescence spectroscope and fluorescence decay life-time measurement.The incorporation of Sm may endow the synthesized phosphor Ca2Gd1-xSbO6∶xSm3+with ions Sm3+as its luminescent centers with the peculiar 4G5/2→6H7/2 transition of Sm3+at 597 nm,so that the synthesized phosphor may emit the orange-red light at 597 nm under the excitation of the light at 407 nm.As the concentration of Sm3+ions increase,the luminous intensity of Ca2GdSbO6∶Sm3+phosphors in-creases first,and then decreases.According to Dexter's theory,the concentration quenching is dominat-ed by the electric dipole-dipole interaction,and the optimum doping of Sm3+ions is concentration x=0.03.The test shows that the color purity of the best-doped sample is about 99.3％,and the color coordi-nates are(0.6146,0.3826).The thermal stability was further studied,and it was found that the emission intensity was only attenuated by 5.56％at 453 K.The above results show that the new red-orange light-emitting Ca2GdSbO6∶Sm3+phosphor is promising to be applied in the field of white LED.
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