Modulated CO Oxidation Activity of M-Doped Ceria (M = Cu, Ti, Zr, and Tb): Role of the Pauling Electronegativity of M

Many properties of dopants have been investigated to explore the key factor that influenced the CO oxidation activity of M-doped ceria (CeM). Nevertheless, these reports were controversial. Herein, the Pauling electronegativity (χ P ) of the M was presented as a convenient guide to screen a proper dopant for ceria. Kinetics results indicated that the T 10 (the temperature when CO conversion reached 10%) of CeM73 catalysts (Ce/M molar ratio was 7/3; M = Cu, Ti, Zr, and Tb) was linearly dependent on the χ P of the M, which could adjust the amount of active lattice oxygen ( A OL ). The A OL was important to catalyst activity because lattice oxygen extraction was the rate-determining step in the overall reaction.