Sensitive determination of thymol based on CeO2 nanoparticle–decorated graphene hybrid film

Abstract

A novel thymol electrochemical sensor based on a CeO₂ nanoparticle–decorated graphene hybrid was introduced. The hybrid was characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The electrochemical behavior of thymol on the CeO₂/graphene modified glassy carbon electrode was investigated in pH 7.0 phosphate buffer solution by cyclic voltammetry and differential pulse voltammetry. Compared with the bare glassy carbon electrode, the proposed electrode showed improved analytical performance characteristics in catalytic oxidation of thymol. Under the selective conditions, the modified electrode showed a linear voltammetric response for the thymol within a concentration range of 1.0 × 10⁻⁷ to 1.8 × 10⁻⁵ mol L⁻¹, and a value of 5.0 × 10⁻⁸ mol L⁻¹ was calculated for the detection limit (S/N = 3). Furthermore, good selectivity with high sensitivity was obtained for the determination of thymol in real samples.