The design and assembly of interlocked supramolecular cages is of interest due to their exquisite topological configuration and excellent performance in a variety of applications. We introduce two carbazole-based ligands L1 and L2, they combine with four distinct half-sandwich rhodium building blocks to form three molecular-tweezer-like compounds, three interlocked cages, tetranuclear macrocycle, and hexanuclear cage. Stacking interactions between carbazole groups facilitate the formation of interlocked structures. Single-crystal X-ray diffraction, Nuclear Magnetic Resonance Spectroscopy and Electrospray Ionization Mass Spectrometry determine their structures. The compounds 5(OTf)12, 6(OTf)12 and 7(OTf)12 exhibit broad-band absorption from Ultraviolet-Visible Spectroscopy to the Near-Infrared regions and remarkable photothermal conversion. They are incorporated into membranes 5'(OTf)12, 6'(OTf)12, and 7'(OTf)12, whose applications in solar energy-driven steam generation are studied. Evaporation rates of 0.77, 1.52, and 1.37 kg·m-2·h-1 are recorded for 5'(OTf)12, 6'(OTf)12, and 7'(OTf)12, respectively, indicating their suitability to collect fresh water from desalination and wastewater treatment.
Lu et al. (Mon,) studied this question.