Density functional theory of SO3 adsorption on the La2CoFeO6 (001) surface

•The conformations of SO3 on the catalyst La2CoFeO6(001) is calculated and most stable adsorption structure is found.•Cohesive energy, adsorption energy, bader charge, deformation charge density and density of states are calculated.•Compared with LaCoO3, the doping of Fe elements can reduces the adsorption energy and charge trans.•Fe doping can enhance anti-sulfur ability and inhibits the next poisoning reaction. In this paper, the method of spin polarization density functional theory and vasp software package are used to simulate the adsorption of SO3 molecules on the surface of La2CoFeO6(001). Through the optimization of different initial adsorption structures, the adsorption energy is compared, the most stable adsorption method is found, and bader charge and state density analysis are performed. The results show that after the CoO2 surface is doped with Fe, the most stable adsorption configuration of SO3 on the surface of CoFeO4 (001) is an O-oriented adsorption at the top position of Fe, and the adsorption energy is −2.0366 eV, which is significantly reduced, and the amount of bader charge transfer is also reduced, and the density change and peak of Fe spin (d) state are larger than that of Co spin (d), indicating that the sulfur resistance of perovskites is significantly enhanced. Therefore, this paper will lay a certain theoretical foundation for the study of perovskite anti-poisoning mechanism, and provide a meaningful reference for further experimental research.