One-step synthesis of N-doped carbon nanotubes-encapsulated Ni nanoparticles for efficient electrochemical CO2 reduction to CO

Electrochemical CO2 reduction (ECR) into high value-added chemicals has attracted continuous attentions in the field of environment and energy storage. Synthesizing stable and efficient electrocatalyst through facile method continues to be a major challenge for ECR. Herein, we produced a carbon nanotubes-encapsulated Ni nanoparticles catalyst through a one-step chemical vapor deposition approach for ECR. Compared with Ni@C and N-C catalysts, the Ni@N-C shows the optimal CO Faraday efficiency (FECO%) of 90% at −0.77 V vs. RHE in the H-type cell. Notably, it shows a high FECO% over 93% within the scope of −0.37 to −0.77 V vs. RHE in the flow cell. The excellent catalytic performance of Ni@N-C demonstrates that N-doped carbon nanotubes coated on Ni nanoparticles are considered as the key step to promoting ECR activity. This work may provide some ideas on the seeking of electrocatalyst in a simple process for efficient ECR.