Synergic effects between boron and nitrogen atoms in BN-codoped C BN fullerenes ( = 1-3) for metal-free reduction of greenhouse NO gas.

The geometries, electronic structures, and catalytic properties of BN-codoped fullerenes C BN ( = 1-3) are studied using first-principles computations. The results showed that BN-codoping can significantly modify the properties of C 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 BN structures. The stepwise addition of N atoms around the B atom improves catalytic activities of C BN in NO reduction. The reduction of NO over CBN and CBN begins with its chemisorption on the B-C bond of the fullerene, followed by the concerted interaction of CO with NO and the release of N. The resulting OCO intermediate is subsequently transformed into a CO molecule, which is weakly adsorbed on the B atom of the fullerene. On the contrary, nitrogen-rich CBN fullerene is found to decompose NO into N 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 NO reduction on CBN fullerene is just 0.28 eV, which is lower than that of noble metals.