Fast synthesis of versatile nanocrystal-embedded hydrogels toward the sensing of heavy metal ions and organoamines

Abstract

We report a facile and rapid approach for the fabrication of CdTe-embedded hydrogels and the selective sensing of these hydrogels toward different analytes. We first synthesized N-acetyl-L-cysteine (NAC)-capped CdTe nanocrystals (NCs) via a microwave-assistance method. Then, taking advantage of frontal polymerization (FP) for fast and easy handling, we facilely prepared CdTe/poly(N-methylolacrylamide) (CdTe/PNMA) and CdTe/poly(N-methylolacrylamide-co-dimethyl diallyl ammonium chloride) (CdTe/poly(NMA-co-DMDAAC)) fluorescent hydrogels. A variety of features for the preparation of CdTe-embedded hydrogels, such as the initiator, solvent concentrations and the ratio of different monomers were thoroughly investigated. The spectroscopic studies reveal that the CdTe-embedded hydrogels prepared via FP exhibit high quantum yield and excellent photoluminescence (PL) stability. By measuring the change in PL properties of the samples, we found that the CdTe/PNMA hydrogels are responsive to different kinds of heavy metal ions, and the CdTe/poly(NMA-co-DMDAAC) fluorescent slices exhibit fluorescent sensing toward organoamines.