Solvothermal reaction of multidentate organic ligand, 5,5′,5″,5‴,5],5]′-[1,2,3,4,5,6-phenylhexamethoxyl]hexaisophthalic acid (H12L), with Cd(NO3)·4H2O produced an anionic 3D metal–organic framework [(CH3)2NH2]4[Cd3(H2L)] (1), which features a novel cage-to-cage connection. Interestingly, the 1D channel, which is stacked by cages, is divided into uniform segments by molecular-scale bricks. The luminescent properties of compound 1 have been explored, which shows that 1 is a potential luminescent sensory material for nitrobenzene.

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By employing a bowl-like tetra­(benzimidazole)­resorcin[4]­arene (TBR4A) ligand, two new polyoxometalate-templated metal–organic frameworks (POMOFs), [Co8Cl14(TBR4A)6]·3­[H3.3SiW12O40]·10DMF·11EtOH·20H2O (1) and [Co3Cl2(TBR4A)2(DMF)4]·[SiW12O40]·2EtOH·3H2O (2), have been prepared under solvothermal conditions (DMF = N,N′-dimethylformamide). 1 shows a 2D cationic layer, whereas 2 exhibits a 3D framework. Remarkably, the Keggin POMs in 1 and 2 were located in the cavities formed by two bowl-like resorcin[4]­arenes in sandwich fashions. Their framework structures were highly dependent on the coordination modes of the TBR4A ligands. To increase the conductivity of POMOFs, the samples of 1 and 2 were loaded on the conductive polypyrrole-reduced graphene oxide (PPy-RGO) via ball milling (1@PG and 2@PG). Then, the obtained composites experienced calcination at a proper temperature to produce 1@PG-A and 2@PG-A. The resulting 1@PG-A and 2@PG-A composites, with improved conductivities, uniform sizes and micropores, exhibited promising electrochemical performance for lithium-ion batteries. We herein proposed a size-controlled route for the rational fabrication of functional POMOFs and their usage in energy fields.