通过溶胶-凝胶法制备出一系列Dy3+掺杂的Y2MgTiO6(YMT∶Dy3+)荧光粉, 并利用X射线衍射仪、扫描电子显微镜、荧光光谱仪对荧光粉的晶体结构、微观形貌及发光性质进行研究和分析。研究结果显示, YMT∶Dy3+荧光粉为双钙钛矿结构, Dy3+掺杂不改变样品的晶体结构。在近紫外光(352 nm)的激发下, 样品的发射光谱显示出典型的Dy3+特征发射峰, 分别是485 nm处的蓝光、578 nm处的黄光, 以及650~700 nm的红光。当Dy3+摩尔浓度x=0.03时, 荧光粉出现浓度猝灭效应, 其浓度猝灭机制为电偶极子-电偶极子相互作用(d-d)。YMT∶Dy3+荧光粉的CIE色坐标明显受到Dy3+的浓度影响, 其中YMT∶0.02Dy3+荧光粉的CIE色坐标为(0.406, 0.407), 位于暖白光区, 可作为一种暖白光荧光粉应用于近紫外激发白光发光二极管(w-LEDs)。

MnO2-modified Pb0.9625Sm0.025(Mg1/3Nb2/3)0.71Ti0.29O3 ceramics were prepared via a solid-state reaction approach. Results of detailed characterizations revealed that the addition of MnO2 has influence on the grain size, and all samples exhibit a pure perovskite structure. As the content of manganese increases, the volume of tetragonal phase increases. The ceramics with 1.5 mol.% MnO2 show a high electro-strain of 0.151% at 2 kV/mm. Therefore, this study provides a new insight into the role of MnO2 addition in tailoring the electrical properties of the Sm-PMN-PT ceramics by acceptor doping.

以高熵合金的研究为背景，将构型熵稳定单相的概念引入无机非金属材料，而逐步发展出一种新的陶瓷材料体系——高熵陶瓷。高熵陶瓷的优点是成分和结构的多样性，这使得其有潜能成为广泛应用的功能材料。本工作采用简单易行的固相烧结法合成了具有尖晶石结构和钙钛矿结构的高熵复相陶瓷，并进一步研究了其物相组成、显微结构、元素含量及价态、和电磁波吸收性能，探究了高熵复相陶瓷的吸波性能随烧结温度的变化规律。结果表明：高熵复相陶瓷可成功制备成型，通过高熵效应能够烧结出2种晶体结构(尖晶石结构和钙钛矿结构)。在1 300 ℃的烧结温度下，存在最大的介电常数，在频率范围为X波段8.2~12.4 GHz时，具备最佳的电磁波吸收性能。

Some of the known binary ABO₃perovskites with ferro- (FE) or antiferroelectric (AFE) at TC and different magnetic phase transitions (PT): ferro-and antiferromagnetic at TN and also some of their solid solutions are considered. Some correlations between their FE or AFE and/or magnetic PTs temperatures, on the one hand, and their interatomic bond A–O strains, on the other hand, have been constructed. It is shown that in the plotted diagrams these temperatures change with a change in δAO values as follows: classical FEs are followed by multiferroics, starting with BiFeO₃ and ending with YVO₃, followed by classical AFEs. At the same time, the temperatures TC and TN experience maxima at the corresponding points for BiFeO₃, then quickly decrease, and the difference between them, TC-TN, basically also decreases, slightly increasing along the way to the point EuTiO₃. which made it possible to systematize these TC and TN.Some of the known binary ABO₃perovskites with ferro- (FE) or antiferroelectric (AFE) at TC and different magnetic phase transitions (PT): ferro-and antiferromagnetic at TN and also some of their solid solutions are considered. Some correlations between their FE or AFE and/or magnetic PTs temperatures, on the one hand, and their interatomic bond A–O strains, on the other hand, have been constructed. It is shown that in the plotted diagrams these temperatures change with a change in δAO values as follows: classical FEs are followed by multiferroics, starting with BiFeO₃ and ending with YVO₃, followed by classical AFEs. At the same time, the temperatures TC and TN experience maxima at the corresponding points for BiFeO₃, then quickly decrease, and the difference between them, TC-TN, basically also decreases, slightly increasing along the way to the point EuTiO₃. which made it possible to systematize these TC and TN.

Cr3+激活荧光粉因其具有远红光和近红外光发射的特性而受到广泛关注。本研究合成了一系列(La,Gd, Y)2MgTiO6∶Cr3+荧光粉, 在345 nm紫外光激发下, 其发射波段为700~900 nm。采用离子取代策略对其光谱进行了调谐, 通过Gd或Y取代La位点, 发射主峰从766 nm分别蓝移至737 nm和757 nm; 150 ℃下的热稳定性从41.7%分别提升至69.1%和67%。系统研究了荧光粉的晶体结构、微观形貌、荧光寿命、热稳定性能和带隙变化等。Gd和Y离子取代会导致晶格收缩, 引起电子云重排效应变化, 最终导致发射光谱蓝移。改性后荧光粉的发射光谱与光敏色素FR(PFR)的吸收(730 nm)具有更好的匹配性, 表明其在植物生长照明中的应用前景, 这也证明通过阳离子取代策略调控Cr3+的发光性能可为未来植物生长灯用荧光粉的研发提供思路。

采用溶胶-水热法合成了具有单一钙钛矿结构的PZT反铁电陶瓷粉体。根据课题组前期的实验结果，选取的水热反应温度为180 ℃，水热反应时间为24 h，矿化剂KOH的浓度为3 mol/L，探讨了Pb的过量值对合成PZT陶瓷粉体的影响。实验发现，Pb的过量值过低，不足以补偿反应过程中Pb的损失量，A位的Pb缺失易导致PZT粉体结晶度的下降，颗粒结晶不完整。随着Pb过量值的增加，颗粒结晶增强，结晶也越完整。当Pb过量增加到10%时，实验获得了结晶良好的PZT粉体。因此，本实验Pb的最佳过量值为10%。

使用一种新的快速热处理的方法制备出Pb(Zr0.52Ti0.48)O3(PZT)薄膜,该方法的主要设备为链式热处理炉,它主要分为三部分,即预热带、加热带和冷却带.溶胶的配制采用先通过减压蒸馏的方法得到干凝胶,再将干凝胶溶解在乙二醇甲醚中的方法得到.对干凝胶作了DSC-TG分析;对薄膜作了X-射线衍射分析,结果为纯的钙钛矿结构的晶相;在10kHz时薄膜的相对介电常数为235,介质损耗小于0.02;C-V特性曲线以及P-E电滞回线显示薄膜具有良好的铁电性能.