Synthesis of Graphene-Supported Hollow AgPd Alloy Nanoparticles and the Application in Detection of Hydrogen Peroxide

In the present study, we demonstrate a novel method to synthesize the graphene-supported AgPd alloy nanocrystals (AgPd/GO) which exhibit unique hollow structure and excellent electrocatalytic activity for H2O2 reduction. The hybrid nanomaterials were synthesized via a two-step method. The graphene supported Ag nanoparticles (Ag/GO) were first synthesized by using sodium citrate as both reducing and stabilizing agents. AgPd alloy nanoparticles supported on graphene (AgPd/GO) were then prepared through a galvanic displacement reaction at 100 °C. The structure of the prepared materials was characterized with UV-visible spectroscopy and transmission electron microscopy (TEM). The electrochemical measurements showed that the AgPd/GO have excellent electrocatalytic activity toward the reduction of hydrogen peroxide. Such hollow Ag/Pd alloy nanoparticles supported on graphene exhibited a low detection limit (1.4 μM) and good linear ranges (0.01–1.4 mM) for H2O2 detection, which render them the suitable electrochemical sensors for hydrogen peroxide detection in practical applications.