Fig. 1. In situ mass spectroscopic examination of iron carbonyls and DFT simulation of its formation via the carbonylation of iron species. (a) Two typical particle growth mechanisms. (b) Signals of m/z using the bar scanning model for 10Fe/hCNC. Reaction conditions: 175 °C, 1.0 MPa CO flow of 10 mL min–1. (c) Signals of m/z = 56 using the trend scanning model. Catalysts: 10Fe/hCNC, 10Fe/hNCNC-1, 10Fe/hNCNC-2 and 10Fe/hNCNC-3. Reaction conditions: 0.10 and 1.0 MPa CO flow of 10 mL min–1. The inset shows an enlarged view of the dashed curves for pCO = 0.10 MPa in the marked region. (d) The free energy diagram for the formation of Fe(CO)5 on a single Fe atom at the pristine or N-doped graphitic plane. The supported Fe single atom without CO adsorption is selected as the referenced zero point. The optimized configurations are presented in Fig. S7.† .
