Catalytic activity of Ru‐N4 doped vacancy fullerenes (Ru‐N4‐C54 and Ru‐N4‐C64) for oxygen reduction and CO oxidation: A density functional theory investigation

Abstract

AbstractIn this work, the catalytic activity of Ru‐N4 doped fullerenes (Ru‐N4‐C54 and Ru‐N4‐C64) for oxygen reduction reaction (ORR) and CO oxidation reaction (COOR) has been systematically investigated from thermodynamics and kinetics by density functional theory (DFT). For ORR, DFT results display that Ru‐N4‐C54 and Ru‐N4‐C64 have satisfactory catalytic behavior both thermodynamically and kinetically. The relative energy curves show that the entire four‐electron process of the most favorable ORR path on Ru‐N4‐C54 and Ru‐N4‐C64 are exothermic, and the activation energies of the rate‐limiting step are 0.60 and 0.40 eV, respectively, which are lower than the calculated value 0.79 eV for Pt (111). For COOR, DFT results reveal that Ru‐N4‐C64 has better catalytic property both thermodynamically and kinetically. The relative energy curve shows that the entire COOR process of the preferred Langmuir–Hinshelwood (LH) mechanism on Ru‐N4‐C64 is exothermic, and the activation energy of the rate‐limiting step is 0.93 eV. Therefore, two hopeful ORR catalysts (Ru‐N4‐C54 and Ru‐N4‐C64) with performance comparable to Pt (111) and one promising COOR catalyst (Ru‐N4‐C64) are identified.