微波固相反应中助熔剂对SrMoO_4∶Tb^(3+)结构和发光性能的影响

Effect of Flux on Structure and Luminescent Properties of SrMoO_4∶Tb^(3+) Synthesized by Microwave Radiation Method

采用微波法以活性炭粒为微波吸收剂成功合成了SrMoO_4∶Tb^(3+)绿色荧光粉,利用X射线粉末衍射仪、扫描电子显微镜、荧光分光光度计等手段对样品进行分析表征,讨论了不同助熔剂对样品的物相结构、微观形貌和发光性质的影响,并确定了助熔剂的最佳用量。结果表明:所合成样品的晶体结构与SrMoO_4相似,属四方晶系结构,I4_1/a空间群。助熔剂K_2CO_3、H_3BO_3或NH_4F的加入有助于改善样品的结晶度和相纯度。未加助熔剂合成的荧光粉颗粒形貌呈不规则片状,添加助熔剂K_2CO_3、H_3BO_3或NH_4F合成的荧光粉颗粒形貌均为类球形。与未加助熔剂合成的荧光粉相比,添加助熔剂NH_4F、K_2CO_3或H_3BO_3后合成的样品发光强度分别提高了57%,21%和18%。

SrMoO4：Tb3＋ green phosphors have been synthesized rapidly by microwave radiation method with aetive carbon particles as microwave absorbent. The as-synthesized samples were analyzed and characterized by X-ray powder diffraction, Scanning electron microscope and Fluorescence spectrophotometer. The effects of different fluxes on the phase structure, morphology and luminescent properties of samples were discussed, and the optimum dosage of flux was confirmed. The results indicate that as-synthesized samples possess the similar structure to that of SrMoO4 with tetragonal system, belonging to space group I41/a. The phase purity and crystallinity of sample can be improved by the addition of K2CO3, HaBO3 or NH4F flux. The phosphor particles without flux have irregular flake-like shape, while those prepared with K2CO3, H3BO3 or NH4F as flux show spherical-like shape. It is found that the emission intensity of SrMoO4： Tb3＋ phosphors with NH4F, K2CO3 or H3BO3 as flux is improved 57%, 21% and 18% respectively than that of the phosphors prepared with no flux.