This study focuses on the enhancement of MIL-117 functionality by incorporating a well-known polyoxometalate (POM), tetrabutylammonium octamolybdate [(n-C₄H₉)₄N]₄[Mo₈O₂₆]. Using an encapsulation method with conventional heating, Mo₈O₂₆⁴⁻ anions were for the first time successfully integrated into MIL-117 tubular channels (Mo₈O₂₆@MIL-117). Comprehensive characterization of the material through FTIR, XRD, BET, FE-SEM, EDX, and XPS confirmed the uniform distribution of Mo₈O₂₆⁴⁻ within MIL-117 without compromising its structural integrity. The Mo₈O₂₆@MIL-117 composite demonstrates exceptional catalytic performance in oxidative C–N bond formation and Paal–Knorr pyrrole synthesis, achieving high yields under optimized conditions with diverse amine substrates. Characterization and stability assessments confirm Mo₈O₂₆@MIL-117 as a robust and recyclable catalyst, maintaining structural integrity and catalytic activity over multiple cycles, highlighting its potential for sustainable applications in synthetic chemistry. The composite material was also evaluated for its efficacy in dye removal, specifically targeting methylene blue (MB) and Rhodamine B (RHB) from aqueous solutions. Mo₈O₂₆@MIL-117 exhibited superior adsorption capacity for MB compared to MIL-117 alone, demonstrating high efficiency even at elevated concentrations. The composite showed improved selectivity towards MB over RHB, highlighting its potential for selective dye removal in wastewater treatment applications.

中文翻译：

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开发用于多相催化和增强染料吸附的多金属氧酸盐负载 MOF


本研究的重点是通过掺入众所周知的多金属氧酸盐 （POM） 八铼酸盐四丁基铵 [（n-C ₄H₉）₄N]₄[Mo₈O₂₆] 来增强 MIL-117 的功能。使用常规加热的包埋方法，Mo₈O₂₆⁴⁻ 阴离子首次成功整合到 MIL-117 管状通道 （Mo₈O₂₆@MIL-117） 中。通过 FTIR、XRD、BET、FE-SEM、EDX 和 XPS 对材料进行全面表征，证实了 Mo₈O₂₆⁴⁻ 在 MIL-117 中均匀分布，而不会影响其结构完整性。Mo₈O₂₆@MIL-117 复合材料在氧化 C-N 键形成和 Paal-Knorr 吡咯合成中表现出优异的催化性能，在具有不同胺底物的优化条件下实现高产率。表征和稳定性评估证实 Mo₈O₂₆@MIL-117 是一种稳健且可回收的催化剂，可在多个循环中保持结构完整性和催化活性，突出了其在合成化学中可持续应用的潜力。还评估了复合材料在去除染料方面的功效，特别是针对水溶液中的亚甲蓝 （MB） 和罗丹明 B （RHB）。与单独的 MIL-117 相比，Mo₈O₂₆@MIL-117 对 MB 表现出优异的吸附能力，即使在高浓度下也表现出高效率。 与 RHB 相比，该复合材料对 MB 的选择性更高，突出了其在废水处理应用中选择性去除染料的潜力。