Unravelling the correlation of dielectric barrier discharge power and performance of Pt/CeO2 catalysts for toluene oxidation

Abstract

Pt/CeO₂ catalysts were modified with non-thermal plasma (dielectric barrier discharge) with different discharge power to investigate the correlation of discharge power and catalyst performance for toluene oxidation. Two volcano peaks (Pt/CeO₂-P2 (4.31 W) and Pt/CeO₂-P6 (9.46 W)) appeared in the activity evaluation curve, whose catalytic activities were dramatically improved after plasma treatment. The results of XRD, BET, HRTEM, XPS and H₂-TPR showed that there were obvious effects on the Pt particle size and CeO₂-rod length, oxygen vacancy concentration and Pt/CeO₂ reducibility by plasma treatment. The Pt atom (slope = 3.0309, R² = 0.8301) was more impacted by the plasma than oxygen vacancies (slope = 2.5225, R² = 0.9130) when the discharge power was between 3.39 and 10.18 W. In addition, the Pt/CeO₂-P6 catalyst (with plasma treatment) still maintained good activity and stability and excellent water resistance. Plasma discharge power could be one of the important factors for catalyst performance optimization of plasma applied in catalyst modification. Therefore, the optimization of the Pt/CeO₂ catalyst with the highest catalytic activity would be modulated by discharge power.