MoS/MWCNT Nanostructure: Enhanced Performance of Screen-Printed Carbon Electrode for Voltammetric Determination of 4-Nitrophenol in Water Samples.

In the present work, we designed a straightforward and disposable voltammetric sensor utilizing a molybdenum disulfide/multi-walled carbon nanotube nanostructure-modified screen-printed carbon electrode (MoS/MWCNTs/SPCE) for 4-nitrophenol (4-NP) determination. The successful synthesis of the MoS/MWCNT nanostructure was characterized using Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EXD) mapping. The electrochemical behavior of 4-NP at the MoS/MWCNTs/SPCE was examined using differential pulse voltammetry (DPV), cyclic voltammetry (CV), and chronoamperometry techniques. The MoS/MWCNTs/SPCE exhibited outstanding electro-catalytic activity for the voltammetric detection of 4-NP. Under optimized conditions, the reduction peak current showed a linear dependence with the concentration of 4-NP in the range of 0.05 to 800.0 µM, and a detection limit (LOD) of 0.01 µM was determined. In addition, the MoS/MWCNTs/SPCE sensor has advantages including repeatability, reproducibility, stability, inexpensiveness, and practical application. The MoS/MWCNTs/SPCE-based sensor was also utilized for the determination of 4-NP in real water specimens.