Design of NdOCl/Nd2O3 nanocomposite for sensitive and selective electrochemical detection of pesticide Carbofuran in environmental and food samples: Explanation of the sensing mechanism

Abstract

Carbofuran (CBF), as a widely used carbamate pesticide, poses significant risks to human health due to its persistence and poor degradability, resulting in soil and water contamination. The existence of a sensitive and reliable sensor for CBF detection is crucial for environmental monitoring. In this study, a neodymium oxychloride/neodymium oxide (NdOCl/Nd2O3) nanocomposite, synthesized via a single-step hydrothermal method, was used for the first time to functionalize the electrode surface and to enhance the electrochemical detection of CBF. Comprehensive morphological (XRPD, ATR-FTIR, XPS and SEM) confirmed nanostructure formation with the mean particle size of (21 ±2) nm (NdOCl) and (14 ±1) nm (Nd2O3). Electrochemical (CV, EIS, DPV) analysis confirmed that NdOCl/Nd2O3 incorporation in the electrode structure significantly improved the electrocatalytic response. This study also includes DFT modeling, which provided detailed insights into the analyte's redox behavior underlying the observed electrochemical response. The resulting sensor exhibited a broad linear detection range (3–200 µM), low detection (0.813 µM) and quantification limits (2.711 µM), and high sensitivity (0.8 µA µM-1 cm-2). Its practical applicability was successfully demonstrated in real sample analysis, achieving excellent recovery rates and validation via UV–Vis spectroscopy. This study highlights the potential of NdOCl/ Nd2O3-modified electrodes as a promising platform for effective CBF monitoring in environmental and food samples.