Cerium-doped iron oxide nanostructures used as a voltammetric sensor for the electrochemical detection of thymol in the presence of bentazone.

Abstract

The Cerium-doped Fe2O3 (Ce-Fe2O3) nanoparticles (NPs) were used to develop a modified electrochemical sensor based on a carbon paste electrode (CPE). In the present study, we used electrochemical techniques (CV, SWV and EIS) to illustrate the analytical behaviour and uses of CPE modified with Ce-Fe2O3 nanoparticles for the simultaneous determination of Thymol (TML) and bentazone (BET). The synthesised Fe2O3 and Ce-doped Fe2O3 NPs were characterized using XRD, FTIR, FESEM with EDX, and TEM techniques. The average crystalline size of the synthesized nanoparticles has been found to be 19 to 30 nm. The Ce-Fe2O3 modified carbon paste electrode (Ce-Fe2O3/CPE) exhibits superior electrochemical performance towards the oxidation of TML as compared to the Fe2O3/CPE. The Ce-Fe2O3/CPE exhibited a linear response towards the detection of TML under investigational conditions, with a detection limit of 1.4052 × 10-8mol L-1. The various parameters such as heterogeneous rate constant (k°), number of electrons transferred (n), electroactive surface area of the electrode (A), and charge transfer resistance (Rct) have been calculated. The sensitivity, long-term stability and reproducibility of the developed sensor were estimated. Analytical validity of the developed electrode has been examined through the real sample analysis using soil sample.