Molecularly imprinted sensor based on 1T/2H MoS2 and MWCNTs for voltammetric detection of acetaminophen

Abstract

1T phase molybdenum disulfide (MoS2) possesses excellent electrical conductivity, 107 times higher than that of 2H phase MoS2. Thus, metallic 1T MoS2 is highly desirable for electrochemical analysis and catalysis. In this study, hybrid 1T/2H MoS2/multi-walled carbon nanotubes (MoS2/MWCNTs) composite was prepared by a facile and simple hydrothermal approach. Powder X-ray diffraction, field emission scanning and transmission electron microscopes, Fourier transform infrared spectroscopy, Raman spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy were used to characterize the composites. The results show that metallic 1T phase MoS2 was formed by the inductive effect of MWCNTs. The high conductivity and large specific surface area of hybrid 1T/2H MoS2/MWCNTs composite endow great catalysis activity in electrochemical analysis. Polypyrrole molecularly imprinted polymer (MIP) film imprinted with acetaminophen (AP) template was electrochemically deposited on glassy carbon electrode (GCE) modified by 1T/2H MoS2/MWCNTs (MoS2/CNTs/GCE) to construct MIP based sensor. The prepared MIP/MoS2/CNTs/GCE sensor shows a sensitive current response towards AP. Through the optimization of the ratio of monomer and template, CV electropolymerization cycles, CV elution cycles, incubation time, and pH, the accessible linear range of 0.01–300 μM was obtained with the limit of detection of 0.003 μM (S/N = 3) by differential pulse voltammetry. In addition, the prepared sensor shows great detecting robustness with excellent selectivity, anti-interference property, reproducibility, and stability. In the urine sample tests, the sensor shows desirable reliability with the recovery rate of 88.1–95.9%.