A fluorescent polyurethane foam based on rhodamine derivative as Fe(III) sensor in pure water

Rhodamine salicylaldehyde was synthesized, and its structure was determined using Fourier transform infrared spectroscopy, 1 H NMR analysis as well as electrospray ionization mass spectrometry. Then a fluorescent polyurethane foam was obtained via incorporation of the prepared rhodamine salicylaldehyde, and the fluorescence sensing behavior for Fe 3+ was systematically investigated. Results showed that the fluorescent polyurethane foam produced higher fluorescence in the presence of Fe 3+ in pure water, due to the coordination for Fe 3+ binding leading to ring-opened amide form. The limit of detection was calculated to be 1.64 × 10 −6 mol L –1 . This fluorescent polyurethane foam can also recognize Fe 3+ with good selectivity. © 2021 Society of Industrial Chemistry.