Chibac-Scutaru Andreea L, Podasca Viorica, Dascalu Ioan A, Melinte Violeta
Polyaddition and Photochemistry Department, Petru Poni Institute of Macromolecular Chemistry, 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania.
Centre of Advanced Research in Bionanoconjugates and Biopolymers (IntelCentru), Petru Poni Institute of Macromolecular Chemistry, 41A GrigoreGhicaVoda Alley, 700487 Iasi, Romania.
Nanomaterials (Basel). 2022 Apr 19;12(9):1402. doi: 10.3390/nano12091402.
Cerium oxide (CeO) nanoparticles were synthesized with a chemical precipitation method in different experimental conditions using cerium nitrate hexahydrate (Ce(NO)·6HO) as a precursor, modifying the solution pH, the reaction time, and Co atoms as dopants, in order to tune the band gap energy values of the prepared samples. The physical characteristics of the synthesized ceria nanoparticles were evaluated by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Vis analyses and photoluminescence measurements. XRD data revealed a pure cubic fluorite structure of CeO NPs, the estimation of crystallite sizes by Scherrer's formula indicates the formation of crystals with dimensions between 11.24 and 21.65 nm. All samples contain nearly spherical CeO nanoparticles, as well as cubic, rhomboidal, triangular, or polyhedral nanoparticles that can be identified by TEM images. The optical investigation of CeO samples revealed that the band gap energy values are between 3.18 eV and 2.85 eV, and, after doping with Co atoms, the of samples decreased to about 2.0 eV. In this study, we managed to obtain CeO NPs with under 3.0 eV by only modifying the synthesis parameters. In addition, by doping with Co ions, the band gap energy value was lowered to 2.0 eV. This aspect leads to promising results that provide an encouraging approach for future photocatalytic investigations.
采用化学沉淀法，以六水合硝酸铈（Ce(NO₃)₃·6H₂O）为前驱体，在不同实验条件下合成了氧化铈（CeO₂）纳米颗粒，通过调节溶液pH值、反应时间以及以钴原子作为掺杂剂，来调整所制备样品的带隙能量值。采用傅里叶变换红外（FT-IR）光谱、X射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、紫外-可见（UV-Vis）分析和光致发光测量等方法对合成的二氧化铈纳米颗粒的物理特性进行了评估。XRD数据显示CeO₂纳米颗粒具有纯立方萤石结构，用谢乐公式估算微晶尺寸表明形成了尺寸在11.24至21.65纳米之间的晶体。所有样品均包含近似球形的CeO₂纳米颗粒，以及可通过TEM图像识别的立方、菱形、三角形或多面体纳米颗粒。对CeO₂样品的光学研究表明，其带隙能量值在3.18 eV至2.85 eV之间，并且在掺杂钴原子后，样品的带隙能量值降至约2.0 eV。在本研究中，我们仅通过改变合成参数就成功获得了带隙能量值低于3.0 eV的CeO₂纳米颗粒。此外，通过掺杂钴离子，带隙能量值降低至2.0 eV。这一结果带来了有前景的成果，为未来的光催化研究提供了一种令人鼓舞的方法。
