LAUSR

We report, for the first time, the possibility of using a silicon atom coordinated carbon nitride fullerene (Si@C24N24) as an efficient catalyst for oxidation of CO by O2 molecule. According to our results, the CO oxidation reaction over Si-C24N24 proceeds via a two-step Langmuir–Hinshelwood mechanism: i.e. (a) CO + O2 → OCOO → CO2 + O and (b) CO + O → CO2. The activation energy for the rate-determining step of this process is only 0.42 eV, which seems to be easily overcome at room temperature. Moreover, spin-crossing between singlet and triplet spin states is found to play an important role in CO oxidation via the Eley–Rideal mechanism. Besides, it is found that the moisture effect can promote the catalytic activity of Si@C24N24 and makes a large decrease in the activation energy of O2 dissociation reaction. GRAPHICAL ABSTRACT