Boosting CO desorption on dual active site electrocatalysts for CO2 reduction to produce tunable syngas

Abstract

The electrochemical conversion of CO 2 to generate syngas (H 2 and CO) is regarded as a promising alternative technique to facilitate CO 2 reduction in the ambient atmosphere. However, it is still a great challenge to acquire high catalytic activity with an adjustable H 2 /CO ratio over a wide range. Here, we construct an electrocatalyst with Fe-containing dual active sites on N-doped porous carbon (Fe/FeN 4 C) to promote a CO 2 reduction reaction for tunable syngas production. The Fe/FeN 4 C catalysts have a positive onset potential (−0.18 V RHE ), approximately 100% of the sum of the Faradaic efficiency (FE) of CO and H 2 , a high total current density (>39.33 mA cm −2 ), and a wide H 2 /CO ratio (1.09∼7.08). Density functional-theory calculations suggest that the Fe single atoms dispersed into the N-doped carbon structure, along with the incorporation of Fe nanoparticles, may decrease the adsorption energy of ∗CO, thus synergistically enhancing the catalytic activity. Fe/FeN 4 C serves as a dual active site catalyst for CO 2 RR to syngas The Fe/FeN 4 C catalyst displays superior CO 2 RR performance toward syngas DFT study confirms the decrease in ∗CO adsorption energy benefits syngas production There is interest in developing active catalysts for the electrochemical conversion of carbon dioxide to syngas with a tunable H 2 /CO ratio. Here, Hua et al. report Fe-containing, N-doped, porous carbon to promote CO 2 reduction for tunable syngas production.