MXene@Cu-BTC/PPy Carbon with MWCNTs@MoS2 Hierarchical Composite for Electrochemical Detection of Anthracene and Phenanthrene in Licorice.

Herbal medicines are particularly vulnerable to contamination by polycyclic aromatic hydrocarbons (PAHs) due to their relatively long growth cycles and multistep processing. This contamination may compromise the efficacy and safety of the prepared herbal slices. The current work innovatively synthesized a hierarchical composite of MXene@Cu-BTC/PPy carbon with MWCNTs@MoS2 (MCuP350/MWCNTs@MoS2) through a sequential in situ growth approach. The material was characterized by using Field Emission Scanning Electron Microscopy (FE-SEM), High-Resolution Transmission Electron Microscopy (HR-TEM), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR) techniques. The electrochemical sensor was prepared based on the MCuP350/MWCNTs@MoS2 composite, which exhibited excellent electrocatalytic activity, displaying good linear responses to both anthracene (ANT) and phenanthrene (PHE). The detection limits of the presented sensor were 0.604 μM (ANT) and 0.240 μM (PHE), respectively. In commonly used herbal medicine of licorice, the effectiveness of the developed sensor for detecting ANT and PHE was validated by the standard addition method, with satisfactory recoveries of 100.36%-104.75% and 97.43%-104.44%, respectively. Additionally, the sensor exhibits high selectivity against the potential interfering substances existing in licorice. These results confirm the feasibility of directly detecting PAHs in licorice via the developed sensor without the need for complex sample pretreatment.