Cu dimer anchored on C2N monolayer: low-cost and efficient Bi-atom catalyst for CO oxidation.

By means of density functional theory (DFT) computations, we systemically investigated CO/O2 adsorption and CO oxidation pathways on a bi-atom catalyst, namely, a copper dimer anchored on a C2N monolayer (Cu2@C2N), and we compared it with its monometallic counterpart Cu1@C2N. The Cu dimer could be stably embedded into the porous C2N monolayer. The reactions between the adsorbed O2 and CO via both bi-molecular and tri-molecular Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) mechanisms were comparably studied, and we found that the bi-atom catalyst Cu2@C2N possessed superior performance toward CO oxidation as compared to the single-atom catalyst Cu1@C2N. Our comparative study suggested that the newly predicted bi-atom catalyst, i.e., a copper dimer anchored on a suitable support is highly active for CO oxidation, which can provide a useful guideline for further developing highly effective and low-cost green nanocatalysts.