Embedded nickel-metallofullerenes (Ni_n@C₆₀) as an effective catalyst for controlled C-C coupling of CO

The C[sbnd]C coupling of CO plays a crucial role in the reduction of CO/CO₂ to C₂₊ compounds. Controlling the activity and active sites of the catalyst proves to be an effective method to achieve controllable C[sbnd]C coupling. By doping metals into fullerene to form endohedral metallofullerenes (EMF), a strategy emerges to achieve unique catalytic activity. Herein, we report that embedded nickel-metallofullerenes (Ni_n@C₆₀) as an efficient catalyst can achieve controllable C[sbnd]C coupling of CO, thereby promoting the generation of C₂ products. The results show that it is thermodynamically feasible for Ni_n clusters to embed into C₆₀ to form Ni_n@C₆₀, electronic structure analysis reveals that Ni_n clusters can activate C₆₀ through electron transfer. Subsequently, research finds that the physically adsorbed CO on C₆₀ and Ni_n@C₆₀ surface can directly form O*C*CO intermediate through controllable C[sbnd]C coupling, with an extremely low activation energy barrier (0.10 ∼ 0.41 eV). Among them, Ni₆@C₆₀ has the lowest activation energy barrier, which is 0.10 eV. This work provides new theoretical insights into C[sbnd]C controllable coupling and the design of novel catalysts for efficient CO/CO₂ conversion.