Facet Effect on Nanosheet Co3O4 Catalysts for Toluene Oxidation: Decisive Role of Co3+ and Reaction-Induced Oxygen Vacancy

Co3O4 is recognized as an advantageous material for harmful VOC abatement. In this paper, three types of Co3O4 catalysts exhibiting either nanosheet morphology or nanosheet tissue structure were synthesized and applied in the combustion of toluene. The characterization results highlight the significance of Co3+ species over surface oxygen. Moreover, the oxygen vacancies of the catalyst formed during the reaction process were found to play a more critical role in influencing the catalytic performance than those that exist in pristine catalysts. Through this study, we gained valuable insights into the facets, Co3+ species, and oxygen vacancies, which hold promising potential for enhancing the development of Co3O4 catalytic material for practical applications in toluene degradation.