The aim of this study was to develop a CuO/La2O3 catalyst to perform the oxidation of ammonia (NH3) to form nitrogen by selective catalytic oxidation (SCO). This catalyst was fabricated by the incipient wetness impregnation technology in a tubular fixed-bed flow quartz reactor. Under optimum conditions, at a temperature of 723K and an oxygen content of 4%, approximately 97% of the NH3 was removed by catalytic oxidation over the CuO/La2O3 (8:2, molar/molar) catalyst, suggesting the presence of a synergetic effect between CuO and La2O3. N-2 was the main product of the NH3-SCO process. The surface properties of the catalyst were analyzed by fluorescent spectroscopy (FS) combined with UV-Vis absorption, dynamic light scattering, zeta potential measurements, cyclic voltammograms (CV), and polarization methods. These studies have shown that the catalytic behavior observed is related to the copper (II) oxide, while rare earth-lanthanum (III) oxide may serve only to provide active sites for the reaction during a catalyzed oxidation experiment. FS and UV-Vis measurements revealed that copper and lanthanum clusters were present on the catalyst surface. Additionally, FS has been applied to evaluate the catalyst yields with fluorescent plots of 280nm, 445nm, and 500nm. These results suggest that FS is an appropriate and effective method to characterize Cu clusters that enhance their intrinsic emission from a CuO/La2O3 catalyst in catalytic treatment systems. The reversible redox ability of these catalysts observed during CV studies may explain their significant activity. Copyright (c) 2013 John Wiley & Sons, Ltd.