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Updated: May 26, 2026
Synthesis of Single-Crystalline Core-Shell Metal-Organic Frameworks
Published on: February 10, 2023
Time-resolved self-assembly of a fullerene-topology core-shell cluster containing 68 uranyl polyhedra
Jie Qiu1, Jie Ling, Audrey Sui
1Department of Civil Engineering and Geological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Abstract:
A complex core-shell cluster consisting of 68 uranyl peroxo polyhedra, 16 nitrate groups, and ~44 K(+) and Na(+) cations was obtained by self-assembly in alkaline aqueous solution under ambient conditions. Crystals formed after a month and were characterized. The cluster, designated as {U(1)⊂U(28)⊂U(40R)}, contains a fullerene-topology cage built from 28 uranyl polyhedra. A ring consisting of 40 uranyl polyhedra linked into five-membered rings and 16 nitrate groups surrounds this cage cluster. Topological pentagons in the cage and ring are aligned, and their corresponding rings of uranyl bipyramids are linked through K(+) cations located between the two shells. A partially occupied U site is located at the center of the cluster. Time-resolved small-angle X-ray scattering and electrospray ionization mass spectrometry demonstrated that the U(28) cage cluster formed in solution within an hour, whereas the U(40R) shell formed around the cage cluster after more than several days.
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