▎ 摘　　要

We report on the construction of PdAg/reduced graphene oxide (rGO)-based electrochemical H2O2 sensors by exploiting the high surface area and fast electron transfer rate of rGO, as well as the high electrocatalytic activity of palladium-silver nanoparticles. The nanocomposites were prepared via a one-step reduction method and characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), Fourier transform spectroscopy (FTIR), and X-ray diffraction (XRD) techniques. The performance of the sensors was evaluated by cyclic voltammetry and chronoamperometry methods. The SEM images showed that the constructed nanocomposites had three-dimensional structure (3D), which both provided large specific surface area for the electrochemical reactions and enhanced the transports of the analyte on the sensors surface. The PdAg/rGO sensors had a high sensitivity of 247.6 +/- 2.7 mu A . mM(-1) . cm(-2) and the 3D structure of rGO along with the high electrocatalytic activity of PdAg nanoparticles allowed the detection of H2O2 in a wide concentration range from 0.05 mM to 28 mM. To evaluate the selectivity of the sensors, the analytical response toward the exposure of H2O2, ascorbic acid, uric acid, and glucose were measured. The practical applicability of PdAg/rGO-based sensor design was studied in human serum. (C) 2016 The Electrochemical Society. All rights reserved.