N-doped peanut-shaped carbon nanotubes for efficient CO2 electrocatalytic reduction

Abstract Using first principles calculations and the computational hydrogen electrode (CHE) model, we present the first systematic study of CO 2 electrocatalytic reduction (CO 2 ER) on recently synthesized peanut-shaped carbon nanotube (FP5N) as well as N-doped FP5N structures. We find FP5N to be metallic with the symmetry of D5h point group. In addition, nitrogen doping in FP5N significantly reduces the overpotential of CO 2 ER. In contrast to graphitic N that reduces CO 2 into CO with an overpotential of 0.65 V, the pyrrolic N, octatomic N and pyridinic N in FP5N convert CO 2 into CH 3 OH with even lower overpotentials of 0.52, 0.52 and 0.60 V, respectively. These values are comparable to those of industrial transition metal catalysts and show that N-doped peanut-shaped carbon nanotubes can outperform conventional N-doped carbon nanomaterials in CO 2 reduction.