Effective Exhaust Gas Treatment Catalyst with Resistance to Sulfur Dioxide_Yang Cheng

Air pollution threatens human health and quality of life. Carbon monoxide (CO), one of the primary ambient air contaminants, is mainly introduced by motor vehicle emissions. To protect human health and comply with emission regulations, catalytic converter has been installed on vehicles. However, low efficiency in cold-start and warm-up period and catalyst poisoning are still key problems for catalytic converter. In this work, treating sulfur dioxide (SO2) as poisoning source, we present how to seek catalyst candidates for conversion process of CO which are stable against SO2. Inspired by the oxygen vacancy tolerance of CeO2 and ABO3 perovskite compounds, all existing binary oxides and ABO3 perovskite compounds were chose as subjects. We constructed phase diagram and analyze stability through interfacial reactions by using Pymatgen. Because the catalytic mechanism could be expressed by oxygen vacancy formation energy, DFT calculations were applied on stable oxides to get oxygen vacancy formation energies on bulk and surface. If one oxide is stable against SO2 and has appropriate oxygen vacancy formation energy, it could be a promising catalyst candidate for exhaust gas treatment. Most importantly, it is an auspicious approach to analyze stability in specific environment (temperature and partial pressure) by constructing phase diagram and considering interfacial reactions through Pymatge