Zdorovets Maxim V, Borgekov Daryn B, Zhumatayeva Inesh Z, Kenzhina Inesh E, Kozlovskiy Artem L
Laboratory of Solid State Physics, The Institute of Nuclear Physics, Ibragimov St., Almaty 050032, Kazakhstan.
Engineering Profile Laboratory, L.N Gumilyov Eurasian National University, Satpayev St., Nur-Sultan 010008, Kazakhstan.
Nanomaterials (Basel). 2022 Jun 29;12(13):2241. doi: 10.3390/nano12132241.
The aim of this work is to study the effect of lanthanum doping on the phase formation processes in ceramics based on CaTiO3, as well as to evaluate the effectiveness of the ceramics as photocatalysts for the decomposition of the organic dye Rhodamine B. The methods used were scanning electron microscopy to evaluate the morphological features of the synthesized ceramics, X-ray diffraction to determine the phase composition and structural parameters, and UV-Vis spectroscopy to determine the optical properties of the ceramics. During the experiments it was found that an increase in the lanthanum dopant concentration from 0.05 to 0.25 mol leads to the formation of the orthorhombic phase La0.3Ca0.7TiO3 and the displacement from the ceramic structure of the impurity phase TiO2, which presence is typical for the synthesized ceramics by solid-phase synthesis. On the basis of the data of the X-ray phase analysis the dynamics of phase transformations depending on concentration of lanthanum was established: CaTiO3/TiO2 → CaTiO3/La2TiO5 → CaTiO3/La0.3Ca0.7TiO3 → La0.3Ca0.7TiO3. During the determination of photocatalytic activity it was found that the formation of La0.3Ca0.7TiO3 phase leads to an increase in the decomposition rate as well as the degree of mineralization.
这项工作的目的是研究镧掺杂对基于CaTiO₃的陶瓷中相形成过程的影响，以及评估该陶瓷作为光催化剂分解有机染料罗丹明B的有效性。所使用的方法包括扫描电子显微镜以评估合成陶瓷的形态特征、X射线衍射以确定相组成和结构参数，以及紫外可见光谱以确定陶瓷的光学性质。在实验过程中发现，镧掺杂剂浓度从0.05摩尔增加到0.25摩尔会导致正交相La₀.₃Ca₀.₇TiO₃的形成以及杂质相TiO₂从陶瓷结构中的位移，TiO₂的存在对于通过固相合成法合成的陶瓷来说是典型的。基于X射线相分析的数据，确定了取决于镧浓度的相变动力学：CaTiO₃/TiO₂ → CaTiO₃/La₂TiO₅ → CaTiO₃/La₀.₃Ca₀.₇TiO₃ → La₀.₃Ca₀.₇TiO₃。在测定光催化活性的过程中发现，La₀.₃Ca₀.₇TiO₃相的形成导致分解速率以及矿化程度的增加。
