Three isomorphous lanthanide–organic polyrotaxane frameworks [Ln(mtpc)1.5(DMA)(H2O)]·2H2O [Ln = Tb (1); Dy (2); Er (3)] were assembled and characterized. In 1, the mtpc ligand transfer absorbed energy to Tb3+ center to emit characteristic fluorescence. 1 can act as a fluorescent probe for selectively detecting nitrobenzene and iron(III) ions through luminescence quenching. Importantly, the detection limit of nitrobenzene is on the 15–150 ppm scale.
