DFT studies of the CH(4)-SCR of NO on Fe-doped ZnAl(2)O(4)(100) surface under oxygen conditions

The catalytic reduction performance of NO on the surface of Fe-doped ZnAl(2)O(4) (100) was calculated based on DFT. The adsorption of NO and other molecules, the change of reaction energy of CH(4) and C(2)H(4) as reducing agents, and the activation energy barrier of CH(4) were studied. It was found that the best adsorption energy of NO is −2.166 eV. Compared with Al and Zn sites, doped Fe atoms are better adsorption catalytic sites. At temperatures of 300 K and 600 K, the molecules will move in the direction of the Fe atoms. O(2) adsorption will repel NO, reduce its adsorption energy, and cause NO to lose electrons and be oxidized. The reaction enthalpy with CH(4) as the reducing agent is −7.02 eV, and with C(2)H(4) is −3.45 eV. Transition state calculations show that O reduces the dissociation barrier of CH(4) by about 2 eV. The smaller adsorption energy and negative reaction enthalpy of the product indicate that the iron-doped ZnAl(2)O(4) has a good catalytic NO potential. This also provides a basis for future research on the catalytic mechanism of different hydrocarbons.