Cysteine-Functionalized Ti3C2 MXene Quantum Dots as Fluorescent Sensors for the Detection of Ag+

Graphical In the present study, the blue fluorescent L-Cys@Ti 3 C 2 MQDs are synthesized using hydrothermal methods, and the preparation process is simple, rapid, and mild. The fluorescence of L-Cys@Ti 3 C 2 MQDs can be effectively quenched by Ag + through a static quenching mechanism, demonstrating high sensitivity and excellent selectivity for Ag + detection. MXene quantum dots (MQDs), an emerging zero-dimensional nanomaterial, have garnered significant attention from researchers due to their distinctive physical and chemical properties. In this study, cysteine-functionalized Ti 3 C 2 MQDs were synthesized using a facile hydrothermal methods, resulting in the functionalized Ti 3 C 2 MQDs exhibiting intense blue fluorescence attributed to size-dependent effects and surface defects. Furthermore, the cysteine-functionalized Ti 3 C 2 MQDs exhibit excitation wavelength-dependent emission behavior and serve as a highly sensitive fluorescent probe for Ag + detection with an impressive low limit of detection (LOD) of 0.015 μM. Moreover, they demonstrate exceptional sensitivity and selectivity in determining Ag + . This study presents a novel approach for the detection of Ag + and highlights the immense potential of cysteine-functionalized Ti 3 C 2 MQDs in environmental applications.