Self-assembled Ti3C2TX MXene/graphene composite for the electrochemical reduction and detection of p-nitrophenol

• Self-assembly method for fabricating D-Ti 3 C 2 T X /GR 2D/2D nanohybrid was developed. • The D-Ti 3 C 2 T X /GR nanohybrid provided an enhanced electro-catalytic activity for the reduction of p -NP. • The proposed sensor based on D-Ti 3 C 2 T X /GR exhibited high sensitivity and low detection limit for p -NP detection. p -Nitrophenol ( p -NP) is an important phenolic environmental pollutant. The development of novel rapid determination methods for p -NP is of significance for environmental monitoring. In this work, a sensitive electrochemical sensor based on Ti 3 C 2 T X MXene/graphene composite was developed to detect p -NP in aqueous samples. Firstly, delaminated titanium carbide (D-Ti 3 C 2 T X ) was successfully prepared via an optimized minimally intensive layer delamination (MILD) method, which was further followed by the self-assembly method to form D-Ti 3 C 2 T X /graphene (D-Ti 3 C 2 T X /GR) composite. The prepared materials were characterized by scanning electron microscopic (SEM), X-ray diffraction (XRD), atomic force microscopy (AFM) and Raman spectroscopy. Then the glassy carbon electrode (GCE) was modified by D-Ti 3 C 2 T X /GR composite to prepare the D-Ti 3 C 2 T X /GR/GCE sensor. The electrochemical behavior of D-Ti 3 C 2 T X /GR/GCE was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronocoulometry. Furthermore, the proposed sensor showed a strong electrochemical response based on the p -NP reduction reaction, benefiting from abundant active sites, fast electron transfer, and excellent electro-catalytic performance of the D-Ti 3 C 2 T X /GR composite. Under the optimal conditions, the D-Ti 3 C 2 T X /GR based electrochemical sensor displayed a linear response in the p -NP concentration range from 1 to 175 μmol·L −1 with a detection limit of 0.16 μmol·L −1 . The anti-interference performance, reproducibility, stability, and recovery in real sample analysis were also further evaluated. This study provided a novel and sensitive method for the rapid determination of p -NP in environmental samples.