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In recent years, ultrafine and nano conversion material on conversion phosphor, infrared detector, fluorescently labeled biomolecules and two-photon confocal microscopy imaging, trademark anti-counterfeiting, etc. are showing great prospect. These materials are widely used in many fields, such as infrared detection, sensors, lasers, and other aspects. These aspects of the application of the special needs of environmentally friendly, high brightness, the granularity reach nanoscale upconversion luminescence material. The perovskite complex oxide having a unique crystal structure, particularly by the structure and properties of the doping after the formation of crystal defects, is applied or may be applied in the solid oxide fuel cell, solid electrolyte, the sensor, high-temperature heating material, solid resistors and alternative redox catalyst for precious metals and many other areas, become a hot research field of chemistry, physics, and materials. Alkaline niobate of the perovskite structure has many excellent properties, for example, ferroelectric, piezoelectric, ionic conduction, the light refraction and the photocatalytic performance. NaNbO with a perovskite structure 3 as the up-conversion materials, not only taking into account the NaNbO 3 crystal has these good properties, but also taking into account NaNbO 3 crystals, there is no such a large group of OH and CO, the phonon energy is low, and easy to prepare, the matrix material is a good up-conversion. The rare-earth ion has a wealth of electronic energy levels and narrow emission line, very suitable as upconversion Launch Center. Therefore, in this paper, we take codoped means to improve the luminescence properties of the sample, focused NaNbO 3 : Er 3 nanocrystals luminescence properties as well as The influence of annealing temperature on the luminescence intensity. NaNbO 3 samples were synthesized by hydrothermal method in this paper first, then, were synthesized by solid phase NaNbO 3 NaNbO 3 : Er < sup> 3 , NaNbO 3 : Sm 3 samples of the samples are given from Er 3 4H11 / 2 , 4S3 / 2 → 4I15 / 2 level transition green emission (517-566 nm) and 4F9 / 2 → 4I15 / 2 level transition red emission (650-680 nm). Its emission intensity is closely related to the annealing temperature, the optimal annealing temperature of 1000 oC. X-ray diffraction results show that the prepared powder NaNbO 3 (the hydrothermal method 200oC and 900oC annealing in the solid-phase method), NaNbO 3 : Er 3 (900oC annealing), NaNbO 3 : Sm 3 (900oC annealing) for the structure of the cubic phase orthorhombic system, when the annealing temperature of 800,950 and 1000 oC, rectangular structure . The powder is excited by the 980 nm LD, respectively launch a center wavelength of about 526 nm green, 547 nm green and 662 nm red (doped with Er 3 ), 526nm green, 550nm green and 660 nm red ( -doped the Sm 3 ) on the conversion fluorescence. Explored of Er 3 , the Sm 3 upconversion luminescence mechanism. Study of the symmetry of the crystal and the annealing temperature NaNbO 3 : Er . 3 upconversion luminescence intensity in the sample, the results show that: with the crystal symmetry reduction and annealing temperature the improvement, NaNbO 3 : Er 3 sample upconversion luminescence intensity enhancement. In addition, prepared by high-temperature solid phase method Er 3 the single blender Er 3 / the Yb 3 codoped Sr 2 TiSi 2 O 8 powder samples, upconversion luminescence intensity with changes in the concentration of the rare earth ion and its upconversion luminescence mechanism.
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