One-pot aqueous method for facile synthesis of platinum-copper bimetallic catalyst based on graphene oxide and its highly enhanced sensing of nitrite

A bimetallic catalyst consisting of platinum-copper (Pt-CuNCs) anchored on graphene oxide (Pt-Cu/GO) was successfully synthesized by a one-pot aqueous method to detect sodium nitrite(NaNO 2 ). The alloy was reduced and grown directly on the surface of graphene oxide(GO), which can maximize the interaction between metals and GO to achieve the enhanced catalytic activity. The transmission electron microscopy (TEM) results showed Pt-CuNCs were of spherical shape with an edge length of 5 ± 2 nm. Cyclicvoltammetry and chronoamperometry were used to test the electrochemical behavior of these nanocomposites and the results showed that Pt-Cu/GO nanocomposites have an excellent catalytic effect for nitrite analysis with a wide linear range of 2.0 × 10 −7 to 9 × 10 −3 mol L −1 , low detection limit 3 μmol L −1 (SNR = 3), and high sensitivity (139.9μA·mM −1 cm −2 ). Furthermore, the sensor exhibited good stability, selectivity, and reproducibility.