Figure 2.
Photoelectron spectra of C 1s, O 1s, and Fe 2p3/2 regions recorded using 4.6 keV photons at 85 (top row) and 700 (bottom row) mbar in the 1CO:4H2 gas mixture at a 2 Ln/min (Ln is the gas volume in liters at atmospheric pressure) total flow. Note that the lower-temperature spectra of the Fe 2p3/2 region are magnified by factors of 3 and 5 for improved visibility of the oxide contribution. Approximate locations of determined species are annotated in the figure. “TP-” and “O-carbide” stand for carbide structures with trigonal prismatic and octahedral sites occupied by carbon atoms, respectively. Examples of spectra fitting are shown for selected measurements at 700 mbar.