Abstract Two-dimensional polymers constitute an emerging class of materials with structurally defined, atomically thin architectures that impart unique optical, electronic, and host–guest properties. Here, we report the synthesis of a crystalline two-dimensional polyketone (2D-PK) via a Friedel–Crafts acylation reaction at a solid–liquid interface on aluminum foil. This interfacial approach yields micrometer-sized sheets composed of highly ordered, stacked layers, as confirmed by SEM, TEM, AFM, and HRTEM analyses. Spectroscopic and diffraction studies—including characteristic shifts in the carbonyl stretching band in IR spectra, sharp solid-state NMR resonances, and well-defined PXRD reflections—further confirm the formation of a crystalline 2D network with an interlayer spacing of 3.54 Å. Beyond structural characterization, 2D-PK exhibits selective supramolecular interactions with organic dyes in aqueous media. Among the investigated analytes, methyl green (MG) shows a markedly stronger affinity for 2D-PK, manifested by pronounced fluorescence enhancement and red-shifted emission, along with distinct changes in NMR, DLS, BET surface area, and UV–Vis absorption profiles. These host–guest interactions arise from a synergistic combination of electrostatic attraction, confinement within polymeric cavities, and charge-transfer-assisted binding, as supported by experimental data and computational simulations. Overall, this study demonstrates that structurally ordered two-dimensional polyketones function as efficient and selective molecular recognition platforms capable of modulating fluorescence responses at low analyte concentrations. These findings highlight the promise of 2D-PKs as versatile materials for chemical sensing, supramolecular chemistry, and future optoelectronic applications.
kazemi et al. (Fri,) studied this question.