白光LED用LiBaBO3:Eu2+材料发光特性研究

采用高温固相法制备了LiBaBO₃:Eu²⁺绿色发光材料.测量了Eu²⁺浓度为1mol%时样品的激发与发射光谱,其发射光谱为双峰宽谱,主峰分别为482和507nm,与理论计算值符合很好;监测482nm发射峰时,对应激发光谱的峰值为287和365nm,监测507nm发射峰时,对应的激发峰为365和405nm.研究了Eu²⁺浓度对材料发射光谱的影响,结果显示,随Eu²⁺浓度的增大,蓝、绿发射峰均发生了     

Eu2+,Mn2+在BaZnP2O7中的发光及Eu2+→Mn2+能量传递

采用高温固相法合成了BaZnP₂O₇:Eu²⁺,Mn²⁺荧光粉,并对其发光性质及Eu²⁺对Mn²⁺的能量传递机理进行了研究.Eu²⁺和Mn²⁺在380 nm和670nm的发射峰分别由Eu²⁺的5d—4f跃迁和Mn²⁺的⁴T₁(^{4关键词： 磷酸盐 2+}')" href="#">Eu²⁺ 2+')" href="#">Mn²⁺ 能量传递     

Eu2+,Mn2+在BaZnP2O7中的发光及Eu2+→Mn2+能量传递

采用高温固相法合成了BaZnP2 01:Eu2 ,Mn2 荧光粉,并对其发光性质及Eu2 对Mn2 的能量传递机理进行了研究.Eu2 和Mn2 在380 am和670 nm的发射峰分别由Eu2 的5d-14f跃迁和Mn2 的4T1(4G)-6A1(6S)跃迁产生.Eu2 对Mn2 的发光有很强的敏化作用,根据Dexter电多极相互作用的能量传递概率公式,判断出BaZnP2O7中Eu2 对Mn2 的能量传递属于电偶极-电四极相互作用引起的共振能量传递.     

绿色荧光粉NaCaPO4：Tb3+的制备与发光特性

采用高温固相法合成了适用于UVLED芯片激发的NaCaPO₄:Tb³⁺绿色荧光粉并对其发光性质进行了研究。该荧光粉的发射峰位于418,440,492,545,586,622nm,分别对应Tb³⁺的⁵D₃→⁷F₅、⁵D₃→⁷F₄、⁵D₄→⁷F₆、⁵D₄→⁷F₅、⁵D₄→⁷F₄、⁵D₄→⁷F₃能级跃迁。其中位于492,545nm的发射峰最强,样品发射很好的绿光。主要激发峰位于380~400nm之间,属于4f→4f电子跃迁吸收,与UVLED芯片的发射相匹配。考察了Tb³⁺掺杂浓度和Li⁺,Na⁺和K⁺作为电荷补偿剂对样品发光性能的影响:Tb³⁺的最佳掺杂浓度为10%,以Li⁺的补偿效果最好。NaCaPO₄:Tb³⁺是一种适用于白光LED的绿色荧光材料。     

Effect of charge compensation on emission spectrum of Ca2SiO4：Dy^3＋ phosphor

The Ca2SiO4：Dy^3＋ phosphor was synthesized by the high temperature solid-state reaction method in air. The emission spectrum of Ca2SiO4：Dy^3＋ phosphor shows several bands at 486, 575, and 665 nm under the 365-nm excitation. The effects of Li^＋, Na^＋, and K^＋ on the emission spectrum of Ca2SiO4：Dy^3＋ phosphor were studied. The results show that the emission spectrum intensity is greatly influenced by Li^＋, Na^＋, and K^＋. The charge compensation concentration corresponding to the maximum emission intensity is different with different charge compensations.     

Preparation and Luminescence Characteristics of Ca3Y2（BO3）4：Eu^3＋ Phosphor

Ca3Y2 （BO3）4：Eu^3＋ phosphor is synthesized by high temperature solid-state reaction method, and the Iuminescence characteristics are investigated. The emission spectrum exhibits two strong red emissions at 613 and 621 nm corresponding to the electric dipole ^5 Do- ^7F2 transition of Eu^3＋ under 365 nm excitation, the reason is that Eu^3＋ substituting for Y^3＋ occupies the non-centrosymmetric position in the crystal structure of Ca3 Y2 （BO3）4. The excitation spectrum for 613 nm indicates that the phosphor can be effectively excited by ultraviolet （UV） （254 nm, 365nm and 400nm） and blue （470nm） light. The effect of Eu^3＋ concentration on the emission intensity of Ca3 Y2 （BO3）4 ：Eu^3＋ phosphor is measured, the result shows that the emission intensities increase with increasing Eu^3＋ concentration, then decrease. The CIE colour coordinates of Ca3Y2 （BO3）4：Eu^3＋ phosphor is （0.639, 0.357） at 15mol% Eu^3＋.     

抽运光偏振态对晶体两波耦合增益的影响

采用非同时读出条件下晶体两波耦合实验装置,以532 nm单频固体激光器为光源,研究了抽运光偏振态对Ce: KNSBN晶体两波耦合有效增益的影响.结果表明:在信号光为e光且入射光夹角为30 °条件下,当抽运光偏振态与e光夹角为10 °时,有效增益最大;通过比较信号光打开与关闭条件下不同偏振态抽运光入射晶体时信号光及抽运光透射光强,分析得出最大增益存在的原因是偏振角为10 °时抽运光的o光分量很好的起到了擦除光扇的作用,抑制了光扇的发生,从而增益最大.取抽运光偏振态与e光夹角为10 °,研究入射光光强比对Ce: KNSBN晶体两波耦合有效增益的影响,结果发现随入射光光强比的增大,有效增益先增大后减小,光强比为1: 50时对应的增益最大为33.8.同时对研究结果进行了相应的物理解释.     

Enhancement of green emission by the codoping A+ (A=Li,Na, K) in Ca2BO3Cl：Tb3+ phosphor

Tb³⁺-doped Ca₂BO₃Cl compounds with different charge compensation approaches are synthesized by a high-temperature solid-state reaction method, and the luminescent properties and Commission Internationale de l'Eclairage (CIE) chromaticity coordinates are systematically characterized. Ca₂BO₃Cl:Tb³⁺ can produce green emission under 376 nm radiation excitation. With codoped A⁺ (A=Li, Na, K) as charge compensators, the relative emission intensities of Ca₂BO₃Cl:Tb³⁺ are enhanced by about 1.61, 1.97, and 1.81 times compared with those of the direct charge balance, which is considered to be due to the effect of the difference in ion radius on the crystal field. The CIE chromaticity coordinates of Ca₂BO₃Cl:Tb³⁺, A⁺ (A=Li, Na, K) are (0.335, 0.584), (0.335, 0.585), and (0.335, 0.585), corresponding to the hues of green. Therefore, A⁺ (A=Li, Na, K) may be the optimal charge compensator for Ca₂BO₃Cl:Tb³⁺.     

电子助进化学气相沉积金刚石中的光发射谱特性

采用蒙特卡罗方法,对以CH₄/H₂为源料气体的电子助进化学气相沉积(EACVD)金刚石中的氢原子(H_α, H_β, H_γ)、碳原子C(2p3s2p2∶λ=165.7 nm)以及CH(A2Δ→X2Π∶λ=420～440 nm)的光发射过程进行了模拟,气体温度随空间的变化采用温度梯度变化,研究了不同反应室气压及衬底温度下的光发射谱特性。结果表明,不同衬底温度下各谱线强度均随气压的增大先增大后减小; 当气压较低时,谱线强度随衬底温度的增大而减少,而气压较高时,谱线强度随衬底温度的增大而增大。     

Ca3SiO5:Eu2+材料光谱特性研究

采用溶胶一凝胶法制备了Ca3SiO5:Eu2+发光材料.测量了材料的激发与发射光谱,结果显示,材料的发射光谱为一峰值位于505 nm处的不对称的宽带谱;监测505nm发射峰,所得材料的激发光谱为一双峰宽谱,峰值为374和397nm,研究了合成条件对Ca3SiO5:Eu2+材料发射光谱的影响,结果显示,随合成温度或合成时间或Eu2+浓度的增大,Ca3 siO5:Eu2+材料发射光谱峰值强度均表现出先增大后减小的趋势,当合成温度为1100℃、合成时间为4 h、Eu2+浓度为0.5 mol%时,Ca3SiO5:Eu2+材料发射光谱峰值强度最大.