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71.
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73.
长余辉发光材料在陶瓷行业的应用研究 总被引:12,自引:4,他引:12
长余辉发光材料和陶/搪瓷材料的结合始于80年代,当时采用的是传统的硫化物体系长余辉发光材料。20世纪90年代,随着多种新型长余辉材料的发现,使性能更佳的长余辉陶/搪瓷制品的开发成为可能。本文介绍新型铝酸盐体系、硅酸盐体系及新型红色长余辉材料应用于低温陶/搪瓷釉料(800-900℃)、中温陶瓷釉料(980-1100℃),及将低温陶/搪瓷釉料、中温陶瓷釉料应用于陶/搪瓷制品的研究,以及将各种新型长余辉材料应用于花纸、玻璃行业中。这种长余辉陶/瓷制品性能稳定、发光强度达到发光粉的80%,发光时间可达12h以上;而且应用工艺简单,可直接用传统的陶/搪瓷制品工艺进行生产。 相似文献
74.
The phosphorescence decay of a series of strontium sulphide microcrystalline phosphors prepared with varying amounts of neodymium
as an activator has been studied at room temperature. The decay obeys the relationI =I
0
t
−b
withb lying between 0·35 and 0·98. The trap depths have been evaluated by peeling off logI-t curves. The results show that the distribution of trap levels is likely to be quasi-uniform and the process of retrapping
during luminescence is negligible. 相似文献
75.
With regard to phosphor thermometry, seven luminescent ceramic materials were synthesised and characterised, namely CaMoO4:Eu3+, CaTiO3:Pr3+, LaPO4:Eu3+, LaVO4:Eu3+, LiAl5O8:Fe3+, TiMg2O4:Mn4+ and ZnGa2O4:Mn2+. In this context, emission spectra and temperature lifetime characteristics are presented. Thus, a survey of phosphors novel for thermography is given in order to encourage further studies and more detailed characterisations of the respective materials. 相似文献
76.
Dr. Yasushi Sato Prof. Dr. Hideki Kato Dr. Makoto Kobayashi Prof. Dr. Takaki Masaki Prof. Dr. Dae‐Ho Yoon Prof. Dr. Masato Kakihana 《Angewandte Chemie (International ed. in English)》2014,53(30):7756-7759
We report a new dicalcium silicate phosphor, Ca2?xEuxSiO4, which emits red light in response to blue‐light excitation. When excited at 450 nm, deep‐red emission at 650 nm was clearly observed in Ca1.2Eu0.8SiO4, the external and internal quantum efficiencies of which were 44 % and 50 %, respectively. The red emission from Ca2?xEuxSiO4 was strongly related to the peculiar coordination environments of Eu2+ in two types of Ca sites. The red‐emitting Ca2SiO4:Eu2+ phosphors are promising materials for next‐generation, white‐light‐emitting diode applications. 相似文献
77.
Ming Zhao Kun Cao Mengjia Liu Jing Zhang Rong Chen Qinyuan Zhang Zhiguo Xia 《Angewandte Chemie (International ed. in English)》2020,59(31):12938-12943
The stability of luminescent materials is a key factor for the practical application in white light‐emitting diodes (LEDs). Poor chemical stability of narrow‐band green‐emitting RbLi(Li3SiO4)2:Eu2+ (RLSO:Eu2+) phosphor hinders their further commercialization even if they have excellent stability against thermal quenching. Herein, we propose an efficient protection scheme by combining the surface coating of amorphous Al2O3 and hydrophobic modification by octadecyltrimethoxysilane (ODTMS) to construct the moisture‐resistant dual‐shelled RLSO:Eu2+@Al2O3@ODTMS composite. The growth mechanisms of both the Al2O3 inorganic layer and the silane organic layer on the phosphor surface are investigated. The results remarkably improve the water‐stability of this narrow‐band green emitter. The evaluation of the white LED by employing this composite as the green component demonstrates that RLSO:Eu2+@Al2O3@ODTMS is a promising candidate for the high‐performance display backlights, and this dual‐shelled strategy provides an alternative method to improve the moisture‐resistant property of humidity‐sensitive phosphors. 相似文献
78.
Electroluminescence has been excited in the phosphor anthracene doped by 9-vinylanthracene (10−4 mole %) at room temperature (300°K). Variation of light output with voltage is governed by the relationB=B
0 exp [−(C/V
1/2)] as in the case of inorganic phosphors. HereB
0 andC are constants andV is the rms value of the voltage applied to the phosphor. Frequency dependence of the electroluminescence has also been studied
at different voltages of the applied electric field. 相似文献
79.
Dr. Hoang‐Duy Nguyen Dr. Chun Che Lin Prof. Dr. Ru‐Shi Liu 《Angewandte Chemie (International ed. in English)》2015,54(37):10862-10866
A facile approach for coating red fluoride phosphors with a moisture‐resistant alkyl phosphate layer with a thickness of 50–100 nm is reported. K2SiF6:Mn4+ particles were prepared by co‐precipitation and then coated by esterification of P2O5 with alcohols (methanol, ethanol, and isopropanol). This route was adopted to encapsulate the prepared phosphors using transition‐metal ions as cross‐linkers between the alkyl phosphate moieties. The coated phosphor particles exhibited a high water tolerance and retained approximately 87 % of their initial external quantum efficiency after aging under high‐humidity (85 %) and high‐temperature (85 °C) conditions for one month. Warm white‐light‐emitting diodes that consisted of blue InGaN chips, the prepared K2SiF6:Mn4+ phosphors, and either yellow Y3Al5O12:Ce3+ phosphors or green β‐SiAlON: Eu2+ phosphors showed excellent color rendition. 相似文献
80.
采用高温固相法分别合成了Sb3+,Bi3+,Zr4+,Si4+共掺杂的YAG∶Ce黄色荧光粉。研究了YAG∶Ce黄色荧光粉的发光强度随元素种类以及微量掺杂浓度的变化情况及相关机理。结果显示,随着元素Sb3+,Bi3+,Zr4+,Si4+掺杂浓度的增加,发射峰强度均表现出先增大后减小的趋势。Sb3+,Bi3+与Ce3+之间存在多极子相互作用和辐射再吸收的能量传递及晶格修复作用,当Sb3+,Bi3+掺杂浓度分别为0.5和0.1 mmol时发射峰强度达到最大值,分别提高了35.5%和44.8%。在YAG∶Ce中由于Zr4+,Si4+的电荷补偿作用,促进Ce4+→Ce3+的转化,从而提高了YAG∶Ce的发光强度。Zr4+,Si4+掺杂浓度分别在0.3和7 mmol时达到最大值,分别提高了27.4%和31.2%。由荧光粉颗粒形貌可知,Sb3+,Bi3+,Zr4+,Si4+元素的微量掺杂能促使晶粒长大,并且近似球型,导致发光强度有明显的提高。 相似文献