Construction of Ir-Co/C nanocomposites and their application in ammonia oxidation reaction

Ammonia electro-oxidation reaction has been paid much attention in recent years because it is widely used in various fields. However, the electro-oxidation of ammonia is a complex process, especially the reaction intermediate has a slow toxic effect on the electrode. To reduce the catalyst poisoning by the absorption of intermediate, the constituent and structure of the catalysts must be deeply researched. In this work, carbon-supported Ir-Co alloy nanocomposites were prepared by pre-deposited method. X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and high resolution transmission electron microscopy (HRTEM) were used to measure the character of the nanocomposites. As expected, the Ir-Co/C nanocomposites revealed superior electro-catalytic activity towards the oxidation of ammonia in 0.4 M NaClO4 solution. The Ir-Co/C-modified GCE demonstrated high sensitivity for ammonia from a range of 0-2.5 M when using amperometry technique to simulate the ammonia-detected environment. At last, real sensor analysis was served to investigate the ammonia-detected performance of the Ir-Co/C, demonstrating high sensitivity and quick response compare to Ir/C and commercial Pt-Ru/C.