Unveiling the Activity Origin of Iron Nitride as Catalytic Material for Efficient Hydrogenation of CO2 to C2+ Hydrocarbons

Developing efficient catalytic materials and unveiling the active species are significant for selective hydrogenation of CO2 to C2+ hydrocarbons. Fe2N@C nanoparticles were reported to exhibit outstanding performance toward selective CO2 hydrogenation to C2+ hydrocarbons (C2+ selectivity: 53.96 %; C-2-C-4(=) selectivity, 31.03 %), outperforming corresponding Fe@C. In situ X-ray diffraction, ex situ Mossbauer and X-ray photoelectron spectra revealed that iron nitrides were in situ converted to highly active iron carbides, which acted as the real active species. Moreover, the combined results of in situ diffuse reflectance infrared Fourier transform spectroscopy and control experiments suggested an in situ formed carbonyl iron-mediated conversion mechanism from iron nitrides to iron carbides.

Automated summary

Fe2N@C nanoparticles show excellent performance in selective hydrogenation of CO2 to C2+ hydrocarbons, with in situ conversion to highly active iron carbides identified as the real active species. Experimental results suggest that carbonyl iron mediates the conversion mechanism from iron nitrides to iron carbides.