Fe-Ni bimetallic composite N-doped carbon catalyst for electrocatalytic reduction of CO2 to produce efficient and controlled syngas

Abstract

The reduction of CO2 to a tunable syngas by electrochemical catalysis for the industrial synthesis of hydrocarbons, alcohols, aldehydes, and other compounds can effectively realize carbon recycling. Herein, in this paper, non-precious metal FeNi precursors were synthesized by solution method, and then a series of FeNi-NC catalysts were obtained by one-step pyrolysis. The results show that on the prepared catalysts, the products of CO2 electroreduction are CO and H2, and the total Faraday efficiency is close to 100 %. Comparison of the prepared catalysts showed that the Fe3Ni7-NC 800 °C had the best selectivity for CO, with a maximum Faraday efficiency of 81.3 % for CO(FECO) generation at a potential of − 0.9 V (vs. RHE), and a current density of − 22.5 mA cm−2 at − 1.2 V. The catalysts had better durability. Moreover, the syngas ratio from 1:1 to 6:1 (CO/H2) can be easily adjusted by controlling the potential applied during the process over a wide potential range, and the resulting syngas in different ratios can be used for the production of chemical raw materials and fuels.