A novel electrochemical ion imprinting sensor modified with carbon nanocomposites and its high selectivity for cadmium ion detection in real samples

Abstract Due to their high toxicity, potential for bioaccumulation and carcinogenicity, heavy metal pollutants have harmed the environment. Cadmium is a dangerous heavy metal that can accumulate easily in the human body. Long‐term exposure to cadmium‐contaminated environments can result in numerous diseases. A novel electrochemical sensor based on multi‐walled carbon nanotubes (MWCNTs)–imprinted polymer and reduced graphene oxide–titanium oxide (rGO@TiO 2 ) is reported which was used to detect cadmium ions in actual samples in a highly sensitive and precise method. By using the surface imprinting technique to adhere the imprinted polymer to the surface of the MWCNTs, the template removal rate and cavity utilization rate are increased. At the same time, the electron transfer rate is increased by the MWCNTs’ superior electrochemical performance and higher conductivity. Transmission electron microscopy was used to characterize the composite's morphology. Cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy were used to describe the imprinted polymer's electrochemical behavior. The findings demonstrate the sensor's excellent cadmium ion selectivity. Under ideal experimental conditions, the electrochemical sensor has a good linear relationship in the range of 10 −9 to 10 −6 mol L −1 , and the detection limit is 1.12 × 10 −9 mol L −1 . The novel sensor offers outstanding repeatability and stability in addition to good selectivity and sensitivity. Eventually, real samples were successfully used to apply the electrochemical sensor for the detection of trace Cd(II) (river water, tap water and rice). © 2023 Society of Industrial Chemistry.