Wang Yunjian, Wu Changjiang, Geng Lei, Chen Shifu
Anhui Key Laboratory of Energetic Materials, College of Chemistry and Materials Science, Huaibei Normal University, Huaibei, 235000, Anhui, P. R. China.
College of Physics and Electronic Information, Huaibei Normal University, P. R. China.
Phys Chem Chem Phys. 2017 Aug 30;19(34):23204-23212. doi: 10.1039/c7cp04521b.
Design of a solid solution with tunable functionality is an attractive strategy toward realizing novel devices with multi-functionalities. In this work, a series of CaCdWO solid solutions in the entire range 0 ≤ x ≤ 1 with tetragonal scheelite structure have been successfully prepared for the first time. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectroscopies indicated that all the nanocrystals have a tetragonal scheelite structure without wolframite phase. Structural refinement data revealed that the lattice volume decreased with the replacement of Ca by Cd ions. UV-Vis diffuse reflectance spectra indicated that optical band gap reduced with the replacement of Ca by Cd ions. Scanning electron microscopic (SEM) images showed that morphologies of the nanocrystals changed with the chemical compositions. The structure evolution of the solid solutions was further investigated by high-resolution transmission electron microscopy (HRTEM). Moreover, the influence of chemical compositions on the photoluminescent and electric performance has been performed and discussed. The reported synthetic approach and findings reported here are important to understand the structure and structure-property relation of scheelite-structured tungstate and molybdate compounds, which has potential applications in the design of other kinds of novel functional materials.
设计具有可调功能的固溶体是实现多功能新型器件的一种有吸引力的策略。在这项工作中，首次成功制备了一系列0≤x≤1范围内具有四方白钨矿结构的CaCdWO固溶体。X射线衍射（XRD）、傅里叶变换红外（FT-IR）和傅里叶变换拉曼（FT-Raman）光谱表明，所有纳米晶体均具有四方白钨矿结构，无黑钨矿相。结构精修数据表明，随着Cd离子取代Ca，晶格体积减小。紫外-可见漫反射光谱表明，随着Cd离子取代Ca，光学带隙减小。扫描电子显微镜（SEM）图像显示，纳米晶体的形态随化学成分而变化。通过高分辨率透射电子显微镜（HRTEM）进一步研究了固溶体的结构演变。此外，还研究并讨论了化学成分对光致发光和电学性能的影响。本文报道的合成方法和研究结果对于理解白钨矿结构钨酸盐和钼酸盐化合物的结构及结构-性能关系具有重要意义，这些化合物在其他新型功能材料的设计中具有潜在应用。
