Electrochemical detection of catechol and hydroquinone based on MXene/MIL-101(Cr)/MWCNTs-COOH.

In this study, MIL-101(Cr) was synthesized using the hydrothermal method. Then, this MOF and MWCNTs-COOH were sequentially loaded onto MXene nanosheets to prepare MXene/MIL-101(Cr)/MWCNTs-COOH. Based on this, an electrochemical sensor capable of simultaneously detecting catechol (CC) and hydroquinone (HQ) was successfully developed. Through the synergistic interaction of its components, the prepared composite effectively addresses the inherent defects of MXene structures, such as structural collapse and susceptibility to oxidation. At the same time, it fully integrates the abundant active sites of MIL-101(Cr), the excellent electronic conductivity of MWCNTs-COOH, and the good dispersibility of MXenes, significantly enhancing the electrochemical detection performance of the sensor. Experimental results indicate that the prepared sensor exhibits good selective recognition of CC and HQ, showing a good linear response in the concentration range of 5.0-187.5 µM. The calculated detection limits (S/N = 3) for CC and HQ were 0.013 µM and 0.017 µM, respectively. Furthermore, the sensor demonstrated excellent resistance to interference and long-term stability. When applied to the detection of CC and HQ in actual samples of Yellow River water and tap water, it yielded good recovery rates, indicating that the sensor has potential for practical applications.