Ali A. Ensafi, A. Mahmoodi, B. Rezaei

A B S T R A C T
In this study, Pd@CeO2-SnO2 nanocomposite was synthesized and various methods such as FE-SEM, TEM, EDS, FT-IR, and XRD were used to characterize the nanocomposite. The electrocatalytic behaviour of the nanocomposite was studied for the reduction of H2O2. After optimization of various experimental parameters including pH, scan rate, rotation rate and potential, the calibration curve was plotted for the reduction reaction of the H2O2 at pHs 7.0 and 8.0. At pH 7.0, the linear range and detection limit were obtained as 0.15–1920 μM and 44 nM, respectively. Also, at pH 8.0, the linear range and detection limit were obtained as 0.12–2170 μM and 36 nM, respectively. In addition, the detection sensitivity of the sensor for the determination of H2O2 at pH 7.0 and 8.0 was 472.40 and 533.07 μA.mM−1. cm-2, respectively. Further, the sensor response to the H2O2 was studied in the presence of various types of potential interference species. The results confirmed the high selectivity of the designed sensor for the reduction of H2O2. Finally, the accuracy and applicability of the H2O2 electrochemical sensor in three different milk samples were evaluated with satisfactory results.

Keywords:
Pd@CeO2-SnO2nanocomposite, Hydrogen peroxide, Amperometry, Non-enzymatic sensing