Fabrication of Stable Cu-Ce Catalyst with Active Interfacial Sites for NOx Elimination by Flame Spray Pyrolysis

Abstract

The complete conversion of NOx to harmless N2 without N2O formation is crucial for the control of air pollution, especially at low temperatures. Cu-based catalysts are promising materials due to their low cost and high activity in NO dissociation, even comparable to noble metals; however, they suffer from low stability. Here, we established a Cu-Ce catalyst in one step with strong metal–support interaction by the flame spray pyrolysis (FSP) method. Almost 100% NO conversion was achieved at 100 °C, and they completely transferred into N2 at a low temperature (200 °C) for the FSP-CuCe catalyst, exhibiting excellent performance in NO reduction by CO reaction. Moreover, the catalytic performance can stay stable, while 23% NO conversion was lost in the same condition for the one made by the co-precipitation (CP) method. This can be attributed to the synergistic effect of abundant active interfacial sites and more flexible surface oxygen created during the FSP process. The flame technology developed here provides an efficient way to fabricate strong metal–support interactions, exhibiting notable potential in the design of stable Cu-based catalysts.