探索通过机械化学合成法制备的负载特定金属氧化物物种的γ-氧化铝的多功能性。

Exploring the Multifunctionality of Mechanochemically Synthesized γ-Alumina with Incorporated Selected Metal Oxide Species.

机构信息

Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242, USA.

Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.

出版信息

Molecules. 2023 Feb 21;28(5):2002. doi: 10.3390/molecules28052002.

DOI:10.3390/molecules28052002

PMID:36903248

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10004189/

Abstract

γ-Alumina with incorporated metal oxide species (including Fe, Cu, Zn, Bi, and Ga) was synthesized by liquid-assisted grinding-mechanochemical synthesis, applying boehmite as the alumina precursor and suitable metal salts. Various contents of metal elements (5 wt.%, 10 wt.%, and 20 wt.%) were used to tune the composition of the resulting hybrid materials. The different milling time was tested to find the most suitable procedure that allowed the preparation of porous alumina incorporated with selected metal oxide species. The block copolymer, Pluronic P123, was used as a pore-generating agent. Commercial γ-alumina (S = 96 m·g), and the sample fabricated after two hours of initial grinding of boehmite (S = 266 m·g), were used as references. Analysis of another sample of γ-alumina prepared within 3 h of one-pot milling revealed a higher surface area (S = 320 m·g) that did not increase with a further increase in the milling time. So, three hours of grinding time were set as optimal for this material. The synthesized samples were characterized by low-temperature N sorption, TGA/DTG, XRD, TEM, EDX, elemental mapping, and XRF techniques. The higher loading of metal oxide into the alumina structure was confirmed by the higher intensity of the XRF peaks. Samples synthesized with the lowest metal oxide content (5 wt.%) were tested for selective catalytic reduction of NO with NH (NH-SCR). Among all tested samples, besides pristine AlO and alumina incorporated with gallium oxide, the increase in reaction temperature accelerated the NO conversion. The highest NO conversion rate was observed for FeO-incorporated alumina (70%) at 450 °C and CuO-incorporated alumina (71%) at 300 °C. The CO capture was also studied for synthesized samples and the sample of alumina with incorporated BiO (10 wt.%) gave the best result (1.16 mmol·g) at 25 °C, while alumina alone could adsorb only 0.85 mmol·g of CO. Furthermore, the synthesized samples were tested for antimicrobial properties and found to be quite active against Gram-negative bacteria, (PA). The measured Minimum Inhibitory Concentration (MIC) values for the alumina samples with incorporated Fe, Cu, and Bi oxide (10 wt.%) were found to be 4 µg·mL, while 8 µg·mL was obtained for pure alumina.

摘要

γ-Alumina 与掺入的金属氧化物物种（包括 Fe、Cu、Zn、Bi 和 Ga）通过液体辅助研磨-机械化学合成合成，使用拟薄水铝石作为氧化铝前体和合适的金属盐。使用不同含量的金属元素（5wt%、10wt%和 20wt%）来调整所得混合材料的组成。测试了不同的研磨时间，以找到最适合的程序，从而制备出掺入选定金属氧化物物种的多孔氧化铝。嵌段共聚物 Pluronic P123 用作孔生成剂。使用商业 γ-Alumina（S=96 m·g）和拟薄水铝石初始研磨两小时后的样品（S=266 m·g）作为参考。对一锅法研磨 3 小时内制备的另一个 γ-Alumina 样品进行分析表明，表面积更高（S=320 m·g），进一步延长研磨时间不会增加。因此，将 3 小时的研磨时间设定为该材料的最佳时间。通过低温 N 吸附、TGA/DTG、XRD、TEM、EDX、元素映射和 XRF 技术对合成样品进行了表征。通过 XRF 峰的强度确认了金属氧化物在氧化铝结构中的更高负载。通过 XRF 峰的强度确认了金属氧化物在氧化铝结构中的更高负载。通过 XRF 峰的强度确认了金属氧化物在氧化铝结构中的更高负载。用最低金属氧化物含量（5wt%）合成的样品进行了选择性催化还原 NO 与 NH（NH-SCR）的测试。在所有测试的样品中，除了原始 AlO 和掺入氧化镓的氧化铝外，随着反应温度的升高，NO 转化率也加快。在 450°C 时，FeO 掺入的氧化铝（70%）观察到最高的 NO 转化率，而在 300°C 时，CuO 掺入的氧化铝（71%）观察到最高的 NO 转化率。还研究了合成样品的 CO 捕获性能，掺入 BiO（10wt%）的氧化铝样品在 25°C 时给出了最佳结果（1.16 mmol·g），而纯氧化铝只能吸附 0.85 mmol·g 的 CO。此外，还对合成样品进行了抗菌性能测试，发现它们对革兰氏阴性菌（PA）非常有效。掺入 Fe、Cu 和 Bi 氧化物（10wt%）的氧化铝样品的最小抑菌浓度（MIC）值为 4µg·mL，而纯氧化铝的 MIC 值为 8µg·mL。