Na(Sr,Ca)VO4:Eu(3+) 荧光粉的光致发光特性

Photoluminescence properties of Na(Sr,Ca)VO4:Eu(3+) phosphors.

作者信息

Lee Dong Gi, Kesavulu C R, Yi Soung Soo, Cho Shinho, Jang Kiwan, Kim Sung Hoon, Jeong Jung Hyun

出版信息

J Nanosci Nanotechnol. 2014 Aug;14(8):5877-80. doi: 10.1166/jnn.2014.8317.

DOI:10.1166/jnn.2014.8317

Abstract

Eu(3+)-activated novel alkaline earth metal (Sr and Ca) vanadate phosphors, Na(Sr(0.97-x), Ca(x))VO4:Eu0.03(3+) (x = 0 to 0.97) has been successfully synthesized using solid state reaction method and characterized by XRD, XPS, FE-SEM, luminescence (PLE, PL and CIE coordinate) and decay rate measurements as a function of Ca ion concentration. Phosphors show a broad excitation band (monitored for (5)D0 --> (7)F2 transition of Eu(3+)) in the 230-430 nm wavelength regions which make them highly suitable for LED chips. Material gives strong emission of Eu(3+) ion (λex = 323 nm) and intensity of this emission increases with increase in the doping concentration of Ca ions until a maximum is reached for Na(Sr0.22, Ca0.75)VO4:Eu0.03(3+) (x = 0.75) phase phosphor. The intensity ratio of (5)D0 --> (7)F2 to (5)D0 --> (7)F1 transition (monochromaticity, R) suggest that local symmetry around the Eu(3+) ion increases with increase in Ca ion concentration, which is responsible for enhanced emission.

摘要

采用固态反应法成功合成了Eu(3+)激活的新型碱土金属（Sr和Ca）钒酸盐荧光粉Na(Sr(0.97 - x), Ca(x))VO4:Eu0.03(3+)（x = 0至0.97），并通过XRD、XPS、FE-SEM、发光（PLE、PL和CIE坐标）以及作为Ca离子浓度函数的衰减率测量对其进行了表征。荧光粉在230 - 430 nm波长区域显示出一个宽激发带（监测Eu(3+)的(5)D0→(7)F2跃迁），这使得它们非常适合用于LED芯片。该材料发出强烈的Eu(3+)离子发射（λex = 323 nm），并且这种发射的强度随着Ca离子掺杂浓度的增加而增加，直到Na(Sr0.22, Ca0.75)VO4:Eu0.03(3+)（x = 0.75）相荧光粉达到最大值。(5)D0→(7)F2与(5)D0→(7)F1跃迁的强度比（单色性，R）表明，随着Ca离子浓度的增加，Eu(3+)离子周围的局部对称性增加，这是发射增强的原因。