Unraveling Catalytic Mechanisms for CO Oxidation on Boron-Doped Fullerene: A Computational Study

Synergic effects between boron and nitrogen atoms in BN-codoped C59-n BN n fullerenes (n = 1-3) for metal-free reduction of greenhouse N2O gas

The geometries, electronic structures, and catalytic properties of BN-codoped fullerenes C_59−nBN_n (n = 1–3) are studied using first-principles computations. The results showed that BN-codoping can significantly modify the properties of C₆₀ fullerene by breaking local charge neutrality and creating active sites. The codoping of B and N enhances the formation energy of fullerenes, indicating that the synergistic effects of these atoms helps to stabilize the C_59−nBN_n structures. The stepwise addition of N atoms around the B atom improves catalytic activities of C_59−nBN_n in N₂O reduction. The reduction of N₂O over C₅₈BN and C₅₇BN₂ begins with its chemisorption on the B–C bond of the fullerene, followed by the concerted interaction of CO with N₂O and the release of N₂. The resulting OCO intermediate is subsequently transformed into a CO₂ molecule, which is weakly adsorbed on the B atom of the fullerene. On the contrary, nitrogen-rich C₅₆BN₃ fullerene is found to decompose N₂O into N₂ and O* species without the requirement for activation energy. The CO molecule then removes the O* species with a low activation barrier. The activation barrier of the N₂O reduction on C₅₆BN₃ fullerene is just 0.28 eV, which is lower than that of noble metals.

The synergic effects between B and N atoms make C₅₇BN₂ and C₅₆BN₃ highly active catalysts for reduction of greenhouse N₂O gas.