The creation of metal nanoclusters with dimensions ranging from subnanometre to ~2 nm for heterogeneous catalysis has received substantial attention. However, synthesizing these structures while retaining surface activity and avoiding aggregation is challenging. Here, we report a reverse double-solvents approach that enables encapsulation of highly catalytically active Pd nanoclusters inside the newly formed discrete organic molecular cage, RCC3. By encapsulating within the open cavities of soluble RCC3 cages, the obtained Pd nanocluster cores are produced with precisely controlled size (~0.72 nm) and show high solubility, excellent dispersibility and accessibility in solution, presenting significantly enhanced catalytic activities towards various liquid-phase catalytic reactions. Moreover, owing to the effective confinement of cage cavities, the as-prepared Pd nanoclusters possess excellent stability and durability. The strategy of encapsulation of metal nanoclusters within soluble porous organic cages is promising for developing stable and active catalysts.
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The authors thank the Ministry of Economy, Trade and Industry, National Institute of Advanced Industrial Science and Technology and Kobe University for financial support. X.Y. is grateful to China Scholarship Council and the Ministry of Education, Culture, Sports, Science and Technology, Japan for a PhD scholarship.
The authors declare no competing interests.
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Yang, X., Sun, JK., Kitta, M. et al. Encapsulating highly catalytically active metal nanoclusters inside porous organic cages. Nat Catal 1, 214–220 (2018). https://doi.org/10.1038/s41929-018-0030-8
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