固溶体结构对Ca_(2-x)Sr_xZn_4Ti_(15)O_(36)∶Pr^(3+)发光性质的影响

Ca2-xSrxZn4Ti15O36∶Pr red long decay phosphor was synthesized by high temperature solid state reaction. Photoluminescence property and crystalline and unit cell parameters of the orthorhombic were investigated by fluorescence spectrophotometer and by powder X-ray diffraction, respectively. The emission intensity at 618 nm changes sharply when the concentration of Sr2+ （x） is less than 0.1 and the emission intensity reaches the maximum when x is equal to 0.007. There is an obviously broad excitation band at 270 nm when x is equal to 0.003 and it disappears gradually when x is over 0.01. The unit cell a parameter of Ca2-xSrxZn4Ti15O36∶Pr decreases while c parameter increases with the increases of the concentration of the doped Sr2+. When x is over 0.1 the value of the unit cell parameters a and c become stable. TL peaks of Ca2Zn4Ti15O36∶Pr, Ca1.993Sr0.007Zn4Ti15O36∶0.002Pr3+, 0.002Na+, are located at 62 ℃, 88 ℃, respectively, which indicates that there are deeper traps in Ca1.993Sr0.007Zn4 Ti15O36∶0.002Pr3+, 0.002Na+.

红色长余辉发光材料Ca_2Zn_4Ti_(15)O_(36)∶Pr^(3+)的合成和发光性质

分别采用高温固相法和溶胶 凝胶法合成了新型红色长余辉发光材料Ca2Zn4Ti15O36∶Pr。高温固相法合成Ca2Zn4Ti15O36需要在1200℃灼烧96h才能形成纯物相。热重分析曲线和X射线衍射分析结果表明:溶胶 凝胶法制得的前驱体在700℃灼烧12h开始形成Ca2Zn4Ti15O36物相;在1000℃灼烧24h得到Ca2Zn4Ti15O36纯物相;最佳反应温度为1000℃,激活剂Pr3+的最佳浓度为0.6mol%,发光强度比高温固相法增强了510%。

Ba_(0.85)Ca_(0.15)Zr_(0.1)Ti_(0.9)O_3/CoFe_2O_4叠层复合陶瓷的制备与磁电耦合效应研究

以CoFe2O4压磁体、掺CuO和CeO2助烧剂的压电体Ba0.85Ca0.15Zr0.1Ti0.9O3为基本叠层材料,采用界面固相熔融渗透法制备了掺助烧剂Ba0.85Ca0.15Zr0.1Ti0.9O3-CoFe2O4叠层复合陶瓷。叠层复合陶瓷的压电压磁相叠层界面结合良好。随着压磁相与压电相厚度比比率的增加,叠层复合陶瓷的饱和磁致伸缩系数–λ从67×10-6增加到134×10-6、压电系数d33从340 pC/N逐渐减小到205 pC/N;磁电耦合系数先增大后减小,在厚度比为2、外磁场为100 mT时得到最大值3200 mV/(cm.mT)。

稀土掺杂Ca_(1.995)Ba_(0.005)Zn_4Ti_(15)O_(36):Pr^(3+),Na^+红色荧光粉的合成和敏化发光

利用溶胶-凝胶法和高温固相法制备了双掺杂的Ca_(1.995)Ba_(0.005)Zn_4Ti_(15)O_(36):Pr^(^(3+)),Na^+发光材料(杂质离子为Sm^(3+),Eu^(3+),Gd^(3+),Tb^(3+),Dy^(3+),Tm^(3+)).实验结果表明溶胶-凝胶法制备的前驱体在1 000℃灼烧24 h,与高温固相法在1 200℃灼烧48 h得到的样品相比,溶胶-凝胶法制备样品的发光性质较好.通过测定样品的激发光谱和发射光谱,发现在Ca_(1.995)Ba_(0.005)Zn_4Ti_(15)O_(36)基质中,Sm^(3+),Eu^(3+),Gd^(3+),Tb^(3+),Dy^(3+)和Tm^(3+)的引入增强了Pr^(3+)的红光发射,其中Eu^(3+)的作用最强.Ca_(1.995)Ba_(0.005)Zn_4Ti_(15)O_(36):0.006 Pr^(3+),0.006Na^+,0.004 Eu^(3+)是一种新型红色长余辉发光材料.