Mn-Driven Energy Level Tuning Suppresses CO Electron Donation and Weakens CO Adsorption for Sabatier-Optimal Reactivity

Element doping modification strategies affect the surface catalytic process and reaction kinetics by altering the local structure and electronic states of catalytic sites. A thorough understanding of the microscopic atomic and electronic structures is conducive to uncovering the catalytic potential of materials. In this study, Mn-doped Co 3 O 4 was synthesized and demonstrated significantly superior catalytic performance, water resistance, and long-term durability compared to pure Co 3 O 4 . Research indicates that Mn doping endows Co 3 O 4 with a relatively high Co 3+ content and oxygen vacancies, which are more conducive to CO catalytic oxidation. Additionally, Mn has fewer d electrons than Co, resulting in a higher d-band center, which could hinder the electron exchange between Mn and CO molecules. Such an effect weakened the CO adsorption, shifting it toward the optimal range defined by the Sabatier principle. This study revealed the controllability of the surface catalytic process of reactant molecules and provided theoretical guidance for the element doping strategy.