fig5

Figure 5. Mechanism study. (A) Models of single-atom Ru supported on different crystal planes of ceria with and without oxygen vacancies. Transition state energy barriers of 1a hydrogenation over single-atom Ru catalysts containing oxygen vacancies on the (111) (B), (100) (C), and (110) (D) planes; (E) Transition state energy barriers of 1a hydrogenation on a single-atom Ru catalyst without oxygen vacancies on the (111) plane; (F) Transition state energy barriers of C_Ar-OCH₃ bond cleavage of 1a over Ru₁/o-CeO₂-ov catalyst.