"Petru Poni" Institute of Macromolecular Chemistry, 700487 Iasi, Romania.
Department of Chemistry, Institute for Research, Innovation and Technological Transfer of the State Pedagogical University "Ion Creanga", MD-2069 Chisinau, Moldova.
Int J Mol Sci. 2023 Mar 29;24(7):6436. doi: 10.3390/ijms24076436.
Neodymium (Nd)-doped ZnO nanostructures with different amounts of Nd were obtained by the electrospinning-calcination method. X-ray diffraction measurements indicated that the prepared nanostructures have a wurtzite structure without undesirable impurities. Nd doping changes the mean crystallite size as well the lattice strain, as proved by Williamson-Hall plots. The ZnO-based nanostructures were tested as photocatalysts for methylene blue (MB) dye and ciprofloxacin (CIP) drug pollutant degradations under visible light irradiation. Corroborating the obtained results, it was found that the reaction rate constant increased almost linearly with the mean crystallite size (from 2.235 × 10 to 3.482 × 10 min) with a variation in the mean crystallite size from 24.2 to 42.1 nm. Furthermore, the best catalyst sample (0.1% Nd-doped ZnO) was used to optimize the photodegradation process of ciprofloxacin, taking into account the pollutant concentration as well as the catalyst dose. The removal efficiency after 120 min was about 100%, with the rate constant of = 5.291·10 min (CIP) and = 4.780·10 min (MB) for the established optimal conditions. Considering the value of the rate constant, the half-life of the reaction ( = ln2/) was evaluated to be about =13 min for CIP and 14.5 min corresponding to MB. Several catalytic cycles were successfully performed without any loss of photocatalytic activity using these nanostructures, demonstrating that the obtained nanostructures have good stability in the leaching processes.
采用静电纺丝-煅烧法制备了不同掺钕量的掺钕氧化锌纳米结构。X 射线衍射测量表明，所制备的纳米结构具有纤锌矿结构，没有不期望的杂质。Nd 掺杂改变了平均晶粒尺寸和晶格应变，这一点通过威廉姆森-霍尔图得到了证明。基于 ZnO 的纳米结构被用作光催化剂，用于在可见光照射下降解亚甲基蓝（MB）染料和环丙沙星（CIP）药物污染物。与获得的结果一致，发现反应速率常数几乎与平均晶粒尺寸线性增加（从 2.235×10 到 3.482×10 min），平均晶粒尺寸从 24.2 到 42.1nm 变化。此外，最佳催化剂样品（0.1%Nd 掺杂 ZnO）用于优化环丙沙星的光降解过程，同时考虑到污染物浓度和催化剂剂量。在 120 分钟后，去除效率约为 100%，在建立的最佳条件下，CIP 的速率常数为 = 5.291·10 min，MB 的速率常数为 = 4.780·10 min。考虑到速率常数的值，反应的半衰期（ = ln2/）评估为 CIP 约为 =13 min，MB 对应于 14.5 min。使用这些纳米结构成功地进行了几次催化循环，没有任何光催化活性损失，证明了所获得的纳米结构在浸出过程中具有良好的稳定性。
