Efficient CO oxidation catalyzed by nickel supported on Ta2O5

CO oxidation has attracted much attention in the field of automotive exhaust treatment and fuel cell industrial process. In this study, NiO loaded on the Ta 2 O 5 was prepared and used to catalyze CO oxidation. And the catalyst NiO/Ta 2 O 5 was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). The catalytic performance was evaluated and the mechanism was analyzed. The catalytic performance has been enhanced greatly by combining NiO with Ta 2 O 5 , the catalyst shows excellent activity in a wide CO concentration from 500 to 10,000 ppm, with CO conversion above 90%. In addition, NiO/Ta 2 O 5 has good stability for CO oxidation with no apparent loss of activity for 8 h. The XPS results show that oxygen defects emerged after reaction. The presence of oxygen defects is responsible for the high catalytic activity. Graphical abstract