▎ 摘　　要

In the present work, we report a single step electrochemical fabrication of a platinum nanoparticle decorated reduced graphene oxide (RGO-PtNPs) composite for enhanced electrochemical sensing of hydrogen peroxide (H2O2). The RGO-PtNPs composite was fabricated by the reduction of graphene oxide modified electrode in an electrolyte solution containing a 0.5 mM K2PtCl6 solution with 1 mM KCl at a constant applied potential of -1.4 V for 300 s. The fabricated composite modified electrode was further characterized by scanning electron microscopy, elemental analysis and cyclic voltammetry. Compared with GO-PtNPs and PtNPs modified electrodes, the RGO-PtNPs composite modified electrode showed an enhanced electrocatalytic activity toward the reduction of H2O2. The amperometric response of the RGO-PtNPs composite modified electrode for the reduction of H2O2 was linear over the concentration ranging from 0.05 to 750.6 mu M with the limit of detection of 16 nM. The sensor reached its steady state current response within 2 s. The sensitivity of the sensor was calculated as 0.686 + 0.072 mu A mu M-1 cm(-2). The proposed sensor showed a satisfactory selectivity in the presence of biologically coactive compounds. In addition, the sensor also showed a good practicability toward the detection of H2O2 in commercial contact lens solutions and human urine samples.