Nickel Nanoparticles with Narrow Size Distribution Confined in Nitrogen-Doped Carbon for Efficient Reduction of CO2 to CO

Facilely tailored electrocatalyst with high-efficiency and durability for carbon dioxide (CO2) to carbon monoxide (CO) conversion is appealing but remains challenging. Herein, small nickel nanoparticles (about 19.4 nm) confined in nitrogen-doped carbon (Ni NPs@N-C) with narrow size distribution are successfully constructed via a facile one-step calcination strategy of Ni containing MOF compounds. By virtue of the protective N-doped graphitized carbon shell and the uniformly distributed fine Ni nanoparticles in a narrow range from 13 to 21 nm, the as-obtained Ni NPs@N-C can exclusively convert CO2 into CO with excellent Faradaic efficiency (FE) of 96.8% at - 1.0 V (vs. RHE), as well as the superior long-term catalytic stability over 24 h. Moreover, a high current density of more than 200 mA cm(-2) with a stable CO FE of 92% can be achieved in a flow cell configuration. This work paves a new way for the facile and potentially scale preparation of small metal nanoparticles for efficient CO2- to-CO conversion. Graphic

Automated summary

In this study, small nickel nanoparticles confined in nitrogen-doped carbon were successfully prepared for highly efficient CO2 to CO conversion, showing excellent Faradaic efficiency and long-term stability. The research provides a new pathway for the facile preparation of metal nanoparticles for efficient CO2 to CO conversion.