Solvothermal synthesis of nitrogen-doped MXene quantum dots for the detection of alizarin red based on inner filter effect

Abstract MXene quantum dots (MQDs) derived from MXene with photoluminescent properties have attracted considerable attention. Herein, nitrogen-doped MQDs (N-MQDs) were constructed by a solvothermal method using Ti3C2 MXene as precursors and o-phenylenediamine (oPD) as the nitrogen source. The morphology, element composition and optical properties of N-MQDs were investigated by transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and spectroscopy etc. The obtained N-MQDs are dispersed quasi-spherical nanoparticles, mainly composed of carbon, oxygen and nitrogen, with yellow fluorescence at 580 nm and quantum yield of 5.42 %. In further, N-MQDs can detect Alizarin Red (ARS) based on inner filter effect (IFE) with linear range and detection limit of 0–80 μM and 1.21 μM, respectively. N-MQDs can detect ARS in real water samples, and were expected to have further applications in the fields of environmental monitoring and biosensing.