Induced synthesis of CeO2 with abundant crystal boundary for promoting catalytic oxidation of gaseous styrene

Abstract

Oxygen vacancies can be used as adsorption-activation sites for reactants, and they can also be used to regulate the electronic structure of catalysts in environmental catalytic oxidation. In the current research on thermal catalytic oxidation, one of the most important issues is the further regulation and design of superior CeO2 catalysts with abundant oxygen vacancies. Herein, this study reveals a crystallization-inducing strategy to manipulate the exposed morphology, crystal planes, and crystal boundary of CeO2 catalysts by adding styrene at the synthesis stage. The characterization results demonstrate that the induced activation of styrene can lead to the formation of abundant Ce-Ce crystal boundaries with rich oxygen vacancies in CeO2-C8H8 catalysts. Among the synthesized induced CeO2-C8H8 catalysts, the short bar-like CeO2-C8H8-130–24 catalyst presented better catalytic activity for styrene oxidation (T90 = 149 °C). Moreover, it is found that such a morphological and crystal boundary structure evolution can improve the durability of CeO2-C8H8-130–24. This study provides a novel strategy for modulating the concentration of oxygen vacancies in CeO2 catalysts.