Highly efficient ozone elimination by metal doped ultra-fine Cu₂O nanoparticles

Nowadays, ozone contamination becomes dominant in air and thus challenges the research and development of cost-effective catalyst. In this study, metal doped Cu₂O catalysts are synthesized via reduction of Cu²⁺ by ascorbic acid in base solutions containing doping metal ions. The results show that compared with pure Cu₂O, the Mg²⁺ and Fe²⁺ dopants enhance the O₃ removal efficiency while Ni²⁺ depresses the activity. In specific, Mg-Cu₂O shows high O₃ removal efficiency of 88.4% in harsh environment of 600,000 mL/(g·hr) space velocity and 1500 ppmV O₃, which is one of the highest in the literature. Photoluminescence and electron paramagnetic spectroscopy characterization shows higher concentration of crystal defects induced by the Mg²⁺ dopants, favoring the O₃ degradation. The in-situ diffuse reflectance Fourier transform infrared spectroscopy shows the intermediate species in the O₃ degradation process change from O₂^2- dominant of pure Cu₂O to O₂^- dominant of Mg-Cu₂O, which would contribute to the high activity. All these results show the promising prospect of the Mg-Cu₂O for highly efficiency O₃ removal.