A Novel Electrochemical Sensing Platform for Detection of Nitrobenzene Using Gadolinium Oxide Nanorods Modified Gold Electrode

Abstract

In the present study, hydrothermally prepared, one-dimensional gadolinium oxide (Gd₂O₃) nanorods were utilized to modify the gold electrode (AuE) for the fabrication of Gd₂O₃/AuE sensor. The nanorod-modified electrode was employed for the sensitive and selective detection of nitrobenzene. The material serves as a highly active electrode material due to its many active sites, high electrocatalytic efficiency, and fast kinetics lead to superior sensing capabilities. The successful synthesis of Gd₂O₃ nanorod was confirmed using different characterization techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), and electron mapping. After fabrication, the shape and phase of NRs did not change. The electrocatalytic performance of Gd₂O₃/AuE sensor against nitrobenzene was investigated through cyclic voltammetric (CV), amperometry, and EIS. As a result, the modified electrode exhibits a low detection limit of 0.0091 µM, a wide linear response of 0.01 to 3 µM, with an excellent sensitivity of 3.09 µA µM⁻¹ cm⁻². In addition, the modified electrode provides an excellent selectivity toward nitrobenzene detection in the presence of various interfering compounds. The fabricated electrode displayed notable storage stability, repeatability, and reproducibility. It has the potential to create an excellent environmental monitoring platform.

Graphical Abstract

Graphical representation of reduction of Nitrobenzene by GdO NRs.