Recently, iChEM Researcher Zhan-Ting Li, Professor at Department of Chemistry, Fudan Univeristy, and Collaborator Yi Liu, Staff Scientist at Molecular Foundry, Lawrence Berkeley National Laboratory, USA, have recently developed a self-assembling strategy to construct the first soluble supramolecular metal-organic framework (SMOF) (Nature Commun. 2016, 7, 11580. DOI: 10.1038/ncomms11580). The new SMOF displayed high homogeneous and heterogeneous photocatalytic activity for H₂ production.

SMOF was constructed from an octahedral [Ru(bpy)₃]²⁺-cored complex and cucurbit[8]uril (CB[8]) in 1:3 molar ratio in water through the encapsulation of CB[8] for the dimers of the appended 4-phenylpyridinium unit. At [Ru²⁺] = 2 mM, SMOF had an average diameter of 164 nm. The solution-phase periodicity of this cubic transition metal-cored supramolecular organic framework (SOF) was confirmed by small-angle X-ray scattering and diffraction experiments, which, as supported by TEM imaging, was commensurate with the periodicity in the solid state. The cubic SMOF adsorbed Wells-Dawson-type POM ([P₂W₁₈O₆₂]6, WD-POM) anion in a one-cage-one-guest manner to give WD-POM@SMOF hybrid assemblies. Upon visible light irradiation at 500 nm, the new hybrids enabled fast multi-electron injection from the photosensitive [Ru(bpy)₃]²⁺ units to redox-active WD-POM units, which led to efficient H₂ production in aqueous media and in organic media (acetonitrile or DMF) with methanol as the sacrificial electron donor.

The demonstrated self-assembly strategy opens the door for the development of new classes of liquid-phase and solid-phase ordered soft porous materials. The research team had recently developed strategies for the construction of supramolecular organic frameworks (SOFs). A recent Feature Article summarized the related advance (Chem. Commun. 2016, 52, 6351. DOI: 10.1039/c6cc02331b).

Paper link: http://www.nature.com/ncomms/2016/160510/ncomms11580/pdf/ncomms11580.pdf