A novel nonenzymatic hydrogen peroxide amperometric sensor based on Pd@CeO2-NH2 nanocomposites modified glassy carbon electrode

Abstract Herein, (3-aminopropyl)triethoxysilane functionalized cerium (IV) oxide (CeO 2 -NH 2 ) supported Pd nanoparticles were synthesized. The nanocomposites were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and High-resolution transmission electron microscopy (HRTEM). The Pd@CeO 2 -NH 2 showed better electrocatalytic response to the reduction of H 2 O 2 than CeO 2 -NH 2 . The fabricated sensor exhibited two linear responses to the reduction of H 2 O 2 . The first one was from 0.001 to 3.276 mM with 0.47 μM of a limit of detection (LOD) (S/N = 3) and excellent sensitivity of 440.72 μA mM −1  cm −2 and the second one was from 3.276 to 17.500 mM with the sensitivity of 852.65 μA mM −1  cm −2 in the optimum conductions. Also, the sensor exhibited 91% of electrocatalytic activity toward H 2 O 2 after having been used for 30 days and the reproducibility was also satisfactory. The sensor response to H 2 O 2 was not affected by ascorbic acid, fructose, glycine, dopamine, arginine, mannose, glucose, uric acid, Mg +2 , Ca +2 , and phenylalanine at the studied potential. Also, the fabricated sensor was used to determine H 2 O 2 in milk samples. The results show that the constructed sensor can be a promising devise for the determination of H 2 O 2 in real samples.