Synthesis of One-Dimensional Ce1−xYxO2−x/2 (0 ≤ x ≤ 1) Solid Solutions and Their Catalytic Properties: The Role of Oxygen Vacancies

Abstract

Oxygen vacancy plays a critical role in most enhanced performances of ceria-based materials. In this study, a facile hydrothermal method was developed for the synthesis of one-dimensional rare-earth doped ceria: Ce1−xYxO2−x/2 (0≤x ≤ 1). The doping concentration could be as high as 90% and the oxygen vacancies therein could be tuned in a wide range. The role of oxygen vacancies on the catalytic properties of these one-dimentional solid solutions had been systematically investigated. It was found that the amounts of the dopant (Y3+) determined the concentration, type, and distribution of oxygen vacancies, which in turn influenced the reducibility and catalytic activity of the solid solutions: in the lightly doped ceria (x ≤ 0.1), oxygen vacancies formed associates with doped ions and improved the reducibility and catalytic activity of materials; with the dopants increased (0.1≤x ≤ 0.5), microdomains or C-type superstructures generated through the ordering of oxygen vacancies formed and decreased the catalyt...