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Three new uranyl―organic coordination frameworks (UO 2 ) 3 -(v-BTC) 2 (H 2 O) 4 (1),(UO 2 ) 6 O(OH)(m-BTC) 2 (m-HBTC) 2 (H 2 O) 2 -(H 3 O)•6H 2 O (2), and (UO 2 ) 2 O(m-BTC)[NH 2 (CH 3 ) 2 ] 2 •H 2 O (3), where v-BTC = 1,2,3-benzenetricarboxylate and m-BTC = 1,2,4-benzenetricarboxylate, have been prepared under hydrothermal conditions. All three compounds possess three-dimensional (3D) architectures. The adjacent carboxylate groups attached to the aromatic ring in the ligands result in strong steric hindrance, and, therefore, they are forced to orient themselves vertically to the aromatic ring. This conformation contributes to the formation of the 3D structures to a great extent. Among these three compounds, 1 has a dense structure, whereas compounds 2 and 3 possess channels that can accommodate water and/or protonated dimethylamine species. Further investigations reveal a microporous adsorption property of compound 2 and a photovoltaic response of compound 3.

Two uranyl-containing organic coordination polymers, (UO2)2(μ2-OH)(pdc)2 Zn(bpy)(Ac)2(H2O)9 (1) (H2pdc = pyridine-2,6-dicarboxylic acid, bpy = 4,4′-bipyridine, HAc = acetic acid) and UO2(pdc)(H2O) (2) have been prepared through a hydrothermal route and characterized by single-crystal X-ray diffraction, thermogravimetric analyses (TGA) and adsorption measurement 1 possesses infinite water cluster chains, which play an important role in the stabilization of the crystal structure. Whereas compound 2 is thermally stable up to at least 350 °C, this material exhibits considerable adsorption capacity for water and methanol upon removal of the guest species in the microporous channels.

A uranium-nickel-organic hybrid compound with micropores has been assembled from a hydrothermal system, and this compound exhibits photocatalytic activities for the degradation of methyl blue as a model pollutant.