Synthesis, characterization, and application of CuO-modified TiO 2 electrode exemplified for ammonia electro-oxidation

In this study, a copper nanoparticle-modified titanium dioxide (CuO–TiO2) catalyst was synthesized using the coprecipitation method with Cu(NO3)2 as the active component for the electrochemical oxidation (ECO) of ammonia (NH3). The voltammetric behavior and characterization of the electrocatalyst, including oxidation behavior, were investigated using linear sweep voltammetry (LSV), polarization, and chronoamperometric measurements, combined with SEM, FTIR, XRD, EEFM and XPS. SEM and XRD spectroscopy revealed that CuO particles were highly dispersed on the anatase phase of the TiO2-supported surface. The XPS and FTIR analysis indicated that CuO was firmly deposited through the linkage of CuOTi bonding to the TiO2 base and the sample exhibiting the stretching vibration mode associated with the CuO bonds of the CuO nanoparticle. Results of EEFM analysis indicate that significant excitation/emission plots located at 218/280 nm is associated with the CuO nanoparticle. The LSV oxidation ability could explain the catalytic activities of the CuO–TiO2 electrocatalysts, and NH3 oxidation peak current on the CuO–TiO2 electrocatalyst increased as scan rates increased, indicating that the adsorption-controlled process occurred at the electrocatalyst.