Revealing the Real Role of Etching during Controlled Assembly of Nanocrystals Applied to Electrochemical Reduction of CO2.

ABSTRACT

In recent years, the use of inexpensive and efficient catalysts for the electrocatalytic CO2 reduction reaction (CO2RR) to regulate syngas ratios has become a hot research topic. Here, a series of nitrogen-doped iron carbide catalysts loaded onto reduced graphene oxide (N-Fe3C/rGO-H) were prepared by pyrolysis of iron oleate, etching, and nitrogen-doped carbonization. The main products of the N-Fe3C/rGO-H electrocatalytic reduction of CO2 are CO and H2, when tested in a 0.5 M KHCO3 electrolyte at room temperature and pressure. In the prepared catalysts, the high selectivity (the Faraday efficiency of CO was 40.8%, at -0.3 V), and the total current density reaches ~29.1 mA/cm2 at -1.0 V as demonstrated when the mass ratio of Fe3O4 NPs to rGO was equal to 100, the nitrogen doping temperature was 800 °C and the ratio of syngas during the reduction process was controlled by the applied potential (-0.2~-1.0 V) in the range of 1 to 20. This study provides an opportunity to develop nonprecious metals for the electrocatalytic CO2 reduction reaction preparation of synthesis and gas provides a good reference.