One-step electroreduction preparation of multilayered reduced graphene oxide/gold-palladium nanohybrid as a proficient electrocatalyst for development of sensitive hydrazine sensor.

A facile and green method for preparation of gold/palladium (Au/Pd) bimetallic nanoparticles interleaved reduced graphene oxide (rGO) composite was presented. One-step electroreduction of Au/Pd precursors and graphene oxide synergistically produced a multilayered and well-structured nanohybrid on glassy carbon electrode, which was explored as a highly efficient electrocatalyst. This operation is easy and controllable, as compared with time-consuming and procedure-tedious hydrothermal synthesis. The morphology and chemical constituents were meticulously characterized. The remarkable electrocatalytic performance of the prepared nanohybrid was demonstrated by detection of a high-risk carcinogen pollutant, hydrazine. By optimizing the preparation condition and investigating the electrochemical behavior, we achieved the sensitive analysis of hydrazine with ultralow oxidation overpotential. Amperometry was employed for constructing the quantitative calibration curve; the steady-state current originating from hydrazine oxidation was proportional to the analytical concentration ranging from 0.1 μM to 200 μM, with the detection limit of 16 nM. Moreover, the nanohybrid displayed considerable anti-interfering ability with respect to hydrazine detection, as a variety of potentially coexisting substances produced negligible electrochemical response in the given analytical condition. Advantages including easy-to-preparation, high sensitivity and favorable selectivity, as well as broad linear response make the present method feasible for monitoring of hydrazine in water environment.