Miao Shihai, Xia Zhiguo, Zhang Jie, Liu Quanlin
School of Materials Sciences and Technology, China University of Geosciences , Beijing 100083, China.
Inorg Chem. 2014 Oct 6;53(19):10386-93. doi: 10.1021/ic501450f. Epub 2014 Sep 25.
We demonstrated that a new intermediate composition of Ba(1.55)Ca(0.45)SiO4 between the orthosilicates Ca2SiO4 and Ba2SiO4 yields the best phosphor hosts, and interesting luminescence properties can be found from the Eu(2+) singly doped and/or Eu(2+)/Mn(2+) codoped Ba(1.55)Ca(0.45)SiO4 phosphors. The phosphors can be excited by near-ultraviolet (nUV) light at wavelengths ranging from 200 to 450 nm matching well with the nUV light-emitting diode (LED) chips. As a result of fine-tuning the activators of different Eu(2+) content and Eu(2+)/Mn(2+) couples with different ratios, tunable full-color emission under UV light excitation can be realized by combining the blue emission (460 nm) and green emission (520 nm) originating from Eu(2+) with the red emission (595 nm) from Mn(2+) in the Ba(1.55)Ca(0.45)SiO4 host lattice. Energy-transfer efficiency between Eu(2+) and Mn(2+) increases and tunable emission can be obtained with increasing Mn(2+) doping content. These results indicate that the Ba(1.55)Ca(0.45)SiO4:Eu(2+),Mn(2+) phosphor will have potential use in nUV chip pumped white LED devices.
我们证明，正硅酸盐Ca2SiO4和Ba2SiO4之间的一种新的中间成分Ba(1.55)Ca(0.45)SiO4产生了最佳的磷光体基质，并且从单掺杂Eu(2+)和/或共掺杂Eu(2+)/Mn(2+)的Ba(1.55)Ca(0.45)SiO4磷光体中可以发现有趣的发光特性。这些磷光体可以被波长范围为200至450nm的近紫外(nUV)光激发，这与nUV发光二极管(LED)芯片很好地匹配。通过微调不同Eu(2+)含量的激活剂以及不同比例的Eu(2+)/Mn(2+)对，在Ba(1.55)Ca(0.45)SiO4主体晶格中，将源自Eu(2+)的蓝色发射(460nm)和绿色发射(520nm)与来自Mn(2+)的红色发射(595nm)相结合，可以在紫外光激发下实现可调谐的全色发射。随着Mn(2+)掺杂含量的增加，Eu(2+)和Mn(2+)之间的能量转移效率提高，并且可以获得可调谐发射。这些结果表明，Ba(1.55)Ca(0.45)SiO4:Eu(2+),Mn(2+)磷光体在nUV芯片泵浦白光LED器件中具有潜在应用。
