Facile synthesis of Pt-Cu bimetallic catalyst on reduced graphene oxide nanosheets and its application for electrochemical sensing.

• The sea urchin-like Pt-Cu bimetallic was synthesized by a one-pot method. • The contact/interaction between nanoparticles and RGO surface was enhanced. • The electrocatalytic activity of the designed hydrazine sensor was investigated. The fabrication and application of bimetallic catalysts are of significance in enhanced electrocatalytic performance. In this work, sea urchin-like Pt-Cu bimetallic catalyst was synthesized by a one-pot aqueous method. The alloy was reduced and grown directly on the surface of reduced graphene oxide (RGO), which can maximize the contact/interaction between metals and RGO to achieve the enhanced catalytic activity. The transmission electron microscopy images revealed that the Pt-Cu bimetallic particles were uniformly dispersed on RGO in the shape of sea urchin-like with the size about ~ 20 nm. A hydrazine electrochemical sensor was built by modifying glassy carbon electrode with Pt-Cu/RGO nanomaterial. The electrochemical experiments showed that the proposed sensor exhibited an excellent performance for hydrazine analysis with a wide linear range of 0.4 μM-12 mM and a low detection limit of 0.13 μ M (S/N = 3). Additionally, the sensor also demonstrated a long term stability, good selectivity and repeatability. [ABSTRACT FROM AUTHOR]