Insight into CH4 formation and chain growth mechanism of Fischer−Tropsch synthesis on θ-Fe3C(0 3 1)

Abstract θ-Fe 3 C has been reported to play a key role in C 2 −C 4 olefins production for Fischer−Tropsch synthesis. In this work, (0 3 1) is confirmed as the most exposed facet of θ-Fe 3 C due to its thermodynamic stability. Investigation on CH 4 formation and C 1 −C 1 coupling reveals that CH 4 formation exhibits a high effective barrier and CH + CH and CH 2  + CH 2 are the dominant chain growth pathways. Δ E eff was employed to quantify the selectivity of CH 4 and C 2+ . The high value of Δ E eff indicates the preference of C 2+ formation to CH 4 . These results will help for the design of selective Fe-based FT catalysts.