Chen Fengfeng, Shen Kui, Chen Junying, Yang Xianfeng, Cui Jie, Li Yingwei
State Key Laboratory of Pulp and Paper Engineering, School of Chemistry and Chemical Engineering and Analytical and Testing Centre, South China University of Technology, Guangzhou 510640, China.
ACS Cent Sci. 2019 Jan 23;5(1):176-185. doi: 10.1021/acscentsci.8b00805. Epub 2019 Jan 7.
The development of a general synthesis approach for creating fine alloyed nanoparticles (NPs) in the pores of metal-organic frameworks (MOFs) shows great promise for advanced synergetic catalysis but has not been realized so far. Herein, for the first time we proposed a facile and general strategy to immobilize ultrafine alloyed NPs within the pores of an MOF by the galvanic replacement of transition-metal NPs (e.g., Cu, Co, and Ni) with noble-metal ions (e.g., Pd, Ru, and Pt) under high-intensity ultrasound irradiation. Nine types of bimetallic alloyed NPs of base and noble metals were successfully prepared and immobilized in the pores of MIL-101 as a model host, which showed highly dispersed and well-alloyed properties with average particle sizes ranging from 1.1 to 2.2 nm and high loadings of up to 10.4 wt %. Benefiting from the ultrafine particle size and high dispersity of Cu-Pd NPs and especially the positive synergy between Cu and Pd metals, the optimized Cu-Pd@MIL-101 exhibited an extremely high activity for the homocoupling reaction of phenylacetylene under unprecedented base- and additive-free conditions and room temperature, affording at least 19 times higher yield (98%) of 1,4-diphenylbuta-1,3-diyne than its monometallic counterparts. This general strategy for preparing various MOF-immobilized alloyed NPs potentially paves the way for the development of highly active metal catalysts for a variety of reactions.
开发一种在金属有机框架（MOF）孔中制备精细合金纳米颗粒（NP）的通用合成方法，对于先进的协同催化具有巨大潜力，但目前尚未实现。在此，我们首次提出了一种简便通用的策略，即在高强度超声辐照下，通过过渡金属NP（如Cu、Co和Ni）与贵金属离子（如Pd、Ru和Pt）的电化置换反应，将超细合金NP固定在MOF的孔中。成功制备了九种贱金属和贵金属的双金属合金NP，并将其固定在作为模型主体的MIL-101孔中，这些NP表现出高度分散且合金化良好的特性，平均粒径范围为1.1至2.2 nm，高负载量可达10.4 wt%。得益于Cu-Pd NP的超细粒径和高分散性，尤其是Cu和Pd金属之间的正协同效应，优化后的Cu-Pd@MIL-101在前所未有的无碱无添加剂条件和室温下，对苯乙炔的均偶联反应表现出极高的活性，1,4-二苯基丁-1,3-二炔的产率（98%）比其单金属对应物至少高19倍。这种制备各种MOF固定化合金NP的通用策略，可能为开发用于各种反应的高活性金属催化剂铺平道路。
