Photoluminescent hydrogel/carbon quantum dots nanocomposite for Fe3+ ions sensing: selectivity and recovery

Polyacrylamide-based hydrogel filled with carbon quantum dots (PAA@CQDs) exhibiting intensive photoluminescence (PL) under UV irradiation was prepared. The exceptional capability of the Fe³⁺ ions to quench PAA@CQDs PL in aqueous solution was found. The PL recovery after repeated quenching was detected when hydrochloric acid was used as a regenerant, thus ensuring the PAA@CQDs reusability as a chemosensor for the Fe³⁺ ions detection in aqueous media.