High-Efficiency Hydrated Tungsten Oxide Nanostructures for Improved Sensitivity in Detecting Fungicides
Davalasab Ilager, Mahesh M. Shanbhag, Shweta J. Malode, Shankara S. Kalanur, Bruno G. Pollet, Adham Aleid, Abdullah N. Alodhayb, Nagaraj P. Shetti
Abstract
The threat of contamination has significantly enhanced in recent years due to the release of more toxins into the environment. Detecting these pollutants requires developing sensitive, selective, and cost-effective electroanalytical techniques for trace analysis. Our current research has created a modified carbon-based sensor to detect and measure fungicides such as thymol (TML) and dichlorophen (DCP). This sensor uses hydrated tungsten oxide (H-WO 3 ) with an immobilized cationic surfactant, cetyltrimethylammonium bromide (CTAB). We synthesized the H-WO 3 nanorods using the hydrothermal method and characterized them using various techniques. The excellent electrocatalytic behavior, high conductance, and large surface-to-volume ratio of the H-WO 3 have significantly improved the voltammetric signal of TML and DCP compared to the bare CPE. We used cyclic voltammetry to determine the optimal conditions, including supporting electrolytes, accumulation time, and CTAB concentration. We also analyzed scan rate and temperature effects to estimate the electrokinetic and thermodynamic activation parameters. The square wave voltammetry technique was applied to find trace levels of TML and DCP, and the developed electrode has a detection limit of 1.43 nM for TML and 7.39 nM for DCP. With this electrochemical method and electrode assembly, we can analyze various fungicides in the future.