Controlled integration of ultrafine metal nanoparticles (MNPs) and metal- organic frameworks (MOFs) has drawn much attention due to their unique physical and chemical properties. However, the development of a one-...Controlled integration of ultrafine metal nanoparticles (MNPs) and metal- organic frameworks (MOFs) has drawn much attention due to their unique physical and chemical properties. However, the development of a one-step strategy for preparing ultrafine MNPs within MOFs still remains a great challenge. Herein, a facile synthetic approach toward the abovementioned composites was developed. In contrast to the conventional approach, these hybrids were prepared by the direct mixing of metal and MOF precursors in the reaction solution assisted by microwave irradiation. Impressively, the Au/MOF-199 composite with uniformly distributed ultrafine Au nanoparticles could be fabricated in only two minutes, and the Au loading could be increased up to a level of 5.13%. The multifunctional Au/MOF-199 catalysts exhibited high turnover numbers (TONs) and turnover frequencies (TOFs) in the three-component coupling reaction of formaldehyde, phenylacetylene, and piperidine (AB-coupling). Owing to the confinement effect of MOF-199, the 5.13%Au/MOF-199 catalyst could be recycled for five runs without serious loss of activity, with no obvious aggregation of Au NPs detected.展开更多
基金The authors acknowledge the financial support from the National Natural Science Foundation of China (Nos. 21573286, 21173269, and 21572688), Ministry ofScience and Technology of China (Nos. 2011BAK15B05 and 2015AA034603), Specialized Research Fund for the Doctoral Program of Higher Education (No. 20130007110003), and Science Foundation of China University of Petroleum, Beijing (No. 2462015YQ0304).
文摘Controlled integration of ultrafine metal nanoparticles (MNPs) and metal- organic frameworks (MOFs) has drawn much attention due to their unique physical and chemical properties. However, the development of a one-step strategy for preparing ultrafine MNPs within MOFs still remains a great challenge. Herein, a facile synthetic approach toward the abovementioned composites was developed. In contrast to the conventional approach, these hybrids were prepared by the direct mixing of metal and MOF precursors in the reaction solution assisted by microwave irradiation. Impressively, the Au/MOF-199 composite with uniformly distributed ultrafine Au nanoparticles could be fabricated in only two minutes, and the Au loading could be increased up to a level of 5.13%. The multifunctional Au/MOF-199 catalysts exhibited high turnover numbers (TONs) and turnover frequencies (TOFs) in the three-component coupling reaction of formaldehyde, phenylacetylene, and piperidine (AB-coupling). Owing to the confinement effect of MOF-199, the 5.13%Au/MOF-199 catalyst could be recycled for five runs without serious loss of activity, with no obvious aggregation of Au NPs detected.