Cation substitution induced novel gehlenite Ca2GaAlSiO7:Eu2+/Ce3+ phosphor with green/blue emission for UV-WLEDs
Cation substitution induced novel gehlenite Ca2GaAlSiO7:Eu2+/Ce3+ phosphor with green/blue emission for UV-WLEDs
复制标题
阳离子取代诱导新型钙黄长石 Ca2GaAlSiO7:Eu2 /Ce3 荧光粉，具有绿色/蓝色发射，适用于 UV-WLED
DOI：
10.1039/c7ra04105e
复制
发表时间：
2017-01-01
期刊：
影响因子：
3.9
通讯作者：
You, Hongpeng
中科院分区：
文献类型：
--
作者：
Jiao, Mengmeng;Xu, Qinfeng;You, Hongpeng
通过将Ga3+离子部分取代黄长石Ca2Al2SiO7中的Al1（2a）和Al2/Si1（4e）位点，首次制备出具有高效绿色和蓝色发射的新型Ca2GaAlSiO7:Eu2+/Ce3+荧光粉。详细研究了这些新样品的结构和发光性质，以及Ga3+取代对Eu-O键长度和共价的减少的影响。激发光谱表明，Eu2+和Ce3+掺杂的Ca2GaAlSiO7样品在紫外范围内具有较宽的激发带，这有利于作为UV- wled荧光粉的应用。在350 nm的辐照下，Ca2GaAlSiO7:Eu2+在510 nm处有强烈的发射峰，而Ca2GaAlSiO7:Ce3+则发出明亮的蓝光。实验结果和分析证实了Eu2+离子的能量迁移机制为电偶极-偶极相互作用。研究了优化后样品的热猝灭机理和量子效率。此外，在紫外芯片上涂覆CaAlSiN3红色荧光粉，获得了白光LED器件。实验结果表明，Ca2GaAlSiO7:Eu2+和Ca2GaAlSiO7:Ce3+样品可能分别作为uv - wled的绿色和蓝色荧光粉具有潜在的价值。
By partially substituting Ga3+ ions at Al1(2a) and Al2/Si1(4e) sites in gehlenite Ca2Al2SiO7, novel Ca2GaAlSiO7:Eu2+/Ce3+ phosphors with efficient green and blue emissions have been prepared for the first time. Structure and luminescence properties of these newly obtained samples have been investigated in detail together with the effect of Ga3+ substitution which has caused a decrement of Eu–O bond length and covalency. The excitation spectra suggested that both the Eu2+ and Ce3+ doped Ca2GaAlSiO7 samples had broad excitation bands in the UV range, which are favourable properties for application as UV-WLED phosphors. Under 350 nm irradiation, the Ca2GaAlSiO7:Eu2+ had intense emission peaking at 510 nm, while Ca2GaAlSiO7:Ce3+ emitted bright blue light. The energy migration mechanism of the Eu2+ ions was confirmed to be electric dipole–dipole interaction in terms of the experimental results and analysis. The thermal quenching mechanism, and quantum efficiency of the composition-optimized samples have been investigated. Moreover, a white LED device has been obtained by coating our prepared phosphors with CaAlSiN3 red phosphor on a UV chip. The experimental results suggested that the Ca2GaAlSiO7:Eu2+ and Ca2GaAlSiO7:Ce3+ samples might have potential value in serving as green and blue phosphors for UV-WLEDs, respectively.