Fabrication of Carbon Nanofiber Incorporated with CuWO₄ for Sensitive Electrochemical Detection of 4-Nitrotoluene in Water Samples

• Published in: Sensors
• Main Authors: Ganesh Abinaya Meenakshi, Subramanian Sakthinathan, Te-Wei Chiu
• Format: Article
• Language: English
• Published: MDPI AG 2023-06-01
• Subjects: CuWO₄; CNF; electrochemical sensor; 4-nitrotoluene; real sample analysis
• Online Access: https://www.mdpi.com/1424-8220/23/12/5668

In the current work, copper tungsten oxide (CuWO₄) nanoparticles are incorporated with carbon nanofiber (CNF) to form CNF/CuWO₄ nanocomposite through a facile hydrothermal method. The prepared CNF/CuWO₄ composite was applied to the electrochemical detection of hazardous organic pollutants of 4-nitrotoluene (4-NT). The well-defined CNF/CuWO₄ nanocomposite is used as a modifier of glassy carbon electrode (GCE) to form CuWO₄/CNF/GCE electrode for the detection of 4-NT. The physicochemical properties of CNF, CuWO₄, and CNF/CuWO₄ nanocomposite were examined by various characterization techniques, such as X-ray diffraction studies, field emission scanning electron microscopy, EDX-energy dispersive X-ray microanalysis, and high-resolution transmission electron microscopy. The electrochemical detection of 4-NT was evaluated using cyclic voltammetry (CV) the differential pulse voltammetry detection technique (DPV). The aforementioned CNF, CuWO₄, and CNF/CuWO₄ materials have better crystallinity with porous nature. The prepared CNF/CuWO₄ nanocomposite has better electrocatalytic ability compared to other materials such as CNF, and CuWO₄. The CuWO₄/CNF/GCE electrode exhibited remarkable sensitivity of 7.258 μA μM⁻¹ cm⁻², a low limit of detection of 86.16 nM, and a long linear range of 0.2–100 μM. The CuWO₄/CNF/GCE electrode exhibited distinguished selectivity, acceptable stability of about 90%, and well reproducibility. Meanwhile, the GCE/CNF/CuWO₄ electrode has been applied to real sample analysis with better recovery results of 91.51 to 97.10%.