A novel electrochemical strategy based on MXene@rGO composite aerogel-doped UiO-66-NH for simultaneous detection of cadmium and lead in grain and water samples.

Herein, a novel electrochemical sensing platform is designed for the simultaneous detection of Cd and Pb, using MXene@rGO composite aerogel-doped UiO-66-NH. The MXene@rGO composite aerogel not only serves as the support structure for UiO-66-NH, but also improves the conductivity of the composite by accelerating the electron transport in the matrix. The amino group of UiO-66-NH offers binding sites for heavy-metal ions, and the existence of PhNH/PhNH in the composite promotes the redox processes of the metal ions to be detected on the electrode surface. The proposed sensing strategy can detect Cd and Pb independently and concurrently, with detection limits of 0.46 ppb and 0.40 ppb, respectively. Remarkably, when this strategy is used for simultaneous detection of Cd and Pb in grain and water samples, it exhibits excellent accuracy and reliability, aligning with the standard method (e.g., AAS and ICP-MS) demonstrating considerable promise in practical applications.