Sn auxiliary agent promoting dispersion of Pt atoms over CeO2 catalysts and DFT calculation

Highly dispersed metal nanoparticles on support are closely related to improving catalytic activity and reducing catalyst cost. Improving the dispersibility of the active components during the preparation of the catalyst is necessary for an unavoidable catalyst sintering in catalytic process. As an important catalytic system in industrial processes, Pt/CeO2 suffers from the sintering problem, therefore, there is an urgent need to improve the redispersion ability of Pt. Our work found that reverse oxygen overflow from CeO2 crystal can facilitate Pt redispersion. More importantly, introduction of Sn into the Pt/CeO2 can reduce the required temperature for Pt redispersion. The dissociation and anchoring of Pt atoms were calculated by DFT, and the redispersion mechanism of Pt on CeO2 support was explained from the perspective of thermodynamics. This work is learnable to study the redispersion of other catalysts.