Sulfation enabled dynamic activation and single-atom extraction against SO2 poisoning

The sulfate formation from the residual SO2 in the industrial exhaust has long been recognized as the primary cause of sulfur poisoning for volatile organic compound oxidative removal. Contrary to the conventional understanding, here we show in situ sulfation enables dynamic activation of Pt1/MnxTi1-xO2 single-atom catalysts against sulfur poisoning, forming highly active Pt1/MnSO4 with Pt1-SO4 motif for excellent SO2-resistance in benzene oxidation. Utilizing state-of-the-art in situ characterizations and theoretical calculations, we identify two distinct sulfur species and their roles in reaction. The (SO3)ads adsorbates block Pt sites causing irreversible deactivation. In contrast, in situ sulfation promotes dynamic transformation of (SO3)ads into MnSO4, and enables Pt single-atom extraction to form Pt1-SO4 motif that prevents SO2 adsorption and preserves exposed Pt single-atom sites for benzene oxidation. This work provides dynamic insights for sulfation of Pt single-atom catalyst against SO2 poisoning and guides the general design of Pt1-SO4 motif for SO2 resistant oxidation. SO2 can deactivate catalysts used to remove harmful organic pollutants from industrial emissions. This study shows that sulfation instead creates active platinum sites that resist sulfur and sustain oxidation.