基于能量传递获取颜色可调型硼酸盐荧光粉及其性能调控

发布时间：2019-06-19 23:37

【摘要】：本文以两种硼酸盐LiBaBO_3和Ba_2B_2O_5为基质,分别通过掺杂不同的稀土离子Eu~(2+)、Eu~(3+)、Tb~(3+)、Ce~(3+)、Sm~(3+)、Dy~(3+),以及过渡金属Mn~(2+)离子,通过高温固相法,合成了多种新型的荧光粉,并详细地研究了合成荧光粉的各种性能。主要的研究内容如下:(1)利用高温固相传统方法,合成了一系列LiBaBO_3:RE(RE=Eu~(2+)/Tb~(3+)/Eu~(3+))荧光粉。通过研究样品的发射光谱、激发光谱,以及寿命衰变曲线等,发现在强还原的气氛下,LiBaBO_3:Eu荧光粉表现出Eu~(2+)的蓝绿色光,而在弱还原的气氛下,LiBaBO_3:Eu荧光粉中,会出现Eu~(2+)与Eu~(3+)离子共存的现象。而且,在空气中烧结LiBaBO_3:Eu,Tb样品时,会出现Tb~(3+)向Eu~(3+)传递能量的现象。而在弱还原条件下,结烧Eu,Tb共掺的LiBaBO_3:样品时,出现了Eu~(2+)离子,Eu~(3+)离子与Tb~(3+)离子共存的现象,并且会发生Eu~(2+)-Tb~(3+)-Eu~(3+)离子的能量传递,得到样品的颜色,也从蓝色到红色可调。也就是说,在LiBaBO_3基质中,Tb~(3+)离子可以作为能量传递的桥梁,来连接Eu~(2+)离子与Eu~(3+)离子,最终得到颜色可调的荧光粉。研究结果表明,Tb~(3+)离子可以起到为Eu~(3+)离子储存能量的作用,而且LiBaBO_3可以作为LED可调颜色的潜在基质。(2)利用高温固相法,合成了一系列单相LiBaBO3:Ce~(3+),AR(R=Eu~(2+),Mn~(2+),Dy~(3+),Sm~(3+),Tb~(3+))以及LiBaBO_3:Tb~(3+),BE(E=Mn~(2+),Dy~(3+),Sm~(3+))荧光粉,并且详细地研究了合成荧光粉的发光性能。通过具体分析得到荧光粉的各种性能,发现在LiBaBO_3基质中,Ce~(3+)离子可以与共掺的Eu~(2+)/Mn~(2+)/Dy~(3+)/Sm~(3+)/Tb~(3+)离子,通过偶极-偶极的相互作用,向这些离子传递能量。除此之外,在LiBaBO_3基质中,当Tb~(3+)离子与其它离子共掺时,共掺的离子会影响Tb~(3+)离子的激发光谱。最终,通过对样品的色坐标的测定,得到了一系列颜色可调的荧光粉。结果表明,LiBaBO_3基质在LED可调颜色的发展上,有着潜在的应用价值。(3)高温固相法,制备了一系列Ce~(3+)/Tb~(3+)/Sm~(3+)掺杂Ba_2B_2O_5基质的荧光粉,并且详细的研究了得到荧光粉的发光特性。在这三种离子单独掺杂在此基质中时,分别表现出蓝色,绿色,以及红色的发光颜色。而当这三种离子中,任何两种离子共掺杂在Ba_2B_2O_5基质中后,Ce~(3+)离子可以向Tb~(3+)离子传递能量,同样Tb~(3+)离子也可以向Sm~(3+)离子传递能量。但是当Ce~(3+)与Sm~(3+)离子共同掺杂在Ba_2B_2O_5基质中,Ce~(3+)离子并不能向Sm~(3+)离子传递能量。而当三种离子同时掺杂在Ba_2B_2O_5基质中以后,Tb~(3+)离子可以作为能量传递的桥梁,来连接Ce~(3+)离子与Sm~(3+)离子。也就是说,在Ba_2B_2O_5基质中,通过Tb~(3+)离子的桥梁作用,实现了三种离子间能量传递的效果,并且最终得到了白色的荧光粉。实验结果表明,Ba_2B_2O_5:Ce,Tb,Sm三掺的白色荧光粉,有应用在白色LED上的潜力。(4)利用高温固相的传统方法,在Ba_2B_2O_5:Ce荧光粉基础上,以Sr/Ca/Mg/Zn部分取代Ba,获得了一系列荧光粉,研究了四类荧光粉的发光特性。通过对发射光谱以及激发光谱的详细分析,发现这一系列阳离子替代荧光粉的最佳激发,都位于360 nm附近,并且随着Ba离子被这四种小半径的离子替代时,发射光谱都先发生了红移,然后又逐渐的蓝移。除此之外,得到的样品色坐标位置,发现随着Ba离子逐渐的被替代成小半径的离子时,样品的颜色发生了很小的改变。因此,通过实验,得到了可以微调样品发射颜色的一种方法。
[Abstract]:Based on the two kinds of borate LiBaBO _ 3 and Ba _ 2B _ 2O _ 5, different rare-earth ions, Eu ~ (2 +), Eu ~ (3 +), Tb ~ (3 +), Ce ~ (3 +), Sm ~ (3 +), Dy ~ (3 +), and transition metal Mn ~ (2 +), were synthesized by high-temperature solid-phase method. And the various properties of the synthesized fluorescent powder are studied in detail. The main contents of the study are as follows: (1) A series of LiBaBO _ 3: RE (RE = Eu ~ (2 +)/ Tb ~ (3 +)/ Eu ~ (3 +)) phosphors are synthesized by high-temperature solid-phase conventional method. The emission spectrum, the excitation spectrum and the life decay curve of the sample were studied. In the atmosphere of strong reduction, the blue-green light of Eu ~ (2 +) was observed by the fluorescent powder of LiBaBO _ 3: Eu, and in the weakly-reduced atmosphere, the LiBaBO _ 3: Eu fluorescent powder. The coexistence of Eu ~ (2 +) and Eu ~ (3 +) ions will be observed. In addition, when the LiBaBO _ 3: Eu, Tb sample is sintered in the air, the phenomenon of the transfer of the Tb ~ (3 +) to the Eu ~ (3 +) is observed. The Eu ~ (2 +) ion, Eu ~ (3 +) ion and Tb ~ (3 +) ion co-exist in the condition of weak reduction, and the energy transfer of Eu ~ (2 +)-Tb ~ (3 +)-Eu ~ (3 +) ion occurs, and the color of the sample is obtained. It is also adjustable from blue to red. In other words, in the LiBaBO _ 3 matrix, the Tb ~ (3 +) ion can be used as a bridge for energy transfer to connect the Eu ~ (2 +) ion and the Eu ~ (3 +) ion, and finally the fluorescent powder with adjustable color is obtained. The results show that the Tb ~ (3 +) ions can be used as the storage energy of the Eu ~ (3 +) ions, and the LiBaBO _ 3 can be used as the potential matrix of the adjustable color of the LED. (2) A series of single-phase LiBaBO3: Ce ~ (3 +), AR (R = Eu ~ (2 +), Mn ~ (2 +), Dy ~ (3 +), Sm ~ (3 +), Tb ~ (3 +), and LiBaBO _ 3: Tb ~ (3 +), BE (E = Mn ~ (2 +), Dy ~ (3 +) and Sm ~ (3 +)) were synthesized by the high-temperature solid-phase method. It is found that the Ce ~ (3 +) ions can be combined with the co-doped Eu ~ (2 +)/ Mn ~ (2 +)/ Dy ~ (3 +)/ Sm ~ (3 +)/ Sm ~ (3 +)/ Tb ~ (3 +) ion in LiBaBO _ 3 matrix, and the energy is transferred to these ions by the interaction of the dipole-dipole. In addition, in the LiBaBO _ 3 matrix, when Tb ~ (3 +) ions are blended with other ions, the co-doped ions will affect the excitation spectrum of Tb ~ (3 +) ions. Finally, a series of color-tunable fluorescent powder is obtained by measuring the color coordinates of the sample. The results show that the LiBaBO _ 3 matrix has potential application value in the development of LED adjustable color. (3) A series of phosphors of Ce ~ (3 +)/ Tb ~ (3 +)/ Sm ~ (3 +)-doped Ba _ 2B _ 2O _ 5 matrix were prepared by high-temperature solid-phase method. When these three ions are individually doped in this matrix, blue, green, and red light-emitting colors are shown, respectively. When any two of these ions are co-doped in the Ba _ 2B _ 2O _ 5 matrix, the Ce ~ (3 +) ions can transfer energy to the Tb ~ (3 +) ions, and the same Tb ~ (3 +) ions can also transfer energy to the Sm ~ (3 +) ions. However, when the Ce ~ (3 +) and Sm ~ (3 +) ions are co-doped in the Ba _ 2B _ 2O _ 5 matrix, the Ce ~ (3 +) ions do not transfer the energy to the Sm ~ (3 +) ions. When the three ions are simultaneously doped in the Ba _ 2B _ 2O _ 5 matrix, the Tb ~ (3 +) ions can be used as the bridge for energy transfer to connect the Ce ~ (3 +) and Sm ~ (3 +) ions. In other words, in the Ba _ 2B _ 2O _ 5 matrix, the effect of the energy transfer between the three ions is realized by the bridge action of the Tb ~ (3 +) ions, and the white fluorescent powder is finally obtained. The experimental results show that the white phosphor doped with Ba _ 2B _ 2O _ 5: Ce, Tb and Sm has the potential to be applied to the white LED. (4) On the basis of Ba _ 2B _ 2O _ 5: Ce phosphor, Ba was replaced with Sr/ Ca/ Mg/ Zn, and a series of phosphors were obtained by using the traditional method of high-temperature solid phase, and the luminescent properties of the four kinds of phosphors were studied. Through a detailed analysis of the emission spectrum and the excitation spectrum, it is found that the best excitation of the series of cations to replace the fluorescent powder is located in the vicinity of 360 nm, and as the Ba ions are replaced by the four small radiuses, the emission spectrum is red shifted and then the blue shift gradually. In addition, the color coordinate position of the sample results in a small change in the color of the sample when the ions of the small radius are gradually replaced with the Ba ions. Thus, a method of fine-tuning the emission color of a sample is obtained by an experiment.
【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O482.31

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