Quasi In Situ Mossbauer Spectroscopy

In situ spectroelectrochemical techniques may be regarded as a type of methodology in which spectroscopic information about the electrode, the electrode/electrolyte interface, and/or the electrolyte solution is sought under conditions in which the potential across the electrode/electrolyte interface is controlled during the data acquisition. There are some instances, however, in which because of intrinsic physical limitations, experiments cannot be conducted in a conventional in situ fashion. Two techniques that appear to fall in such a category, referred to hereafter as quasi in situ, will be presented in the following sections. 

FIGURE 7. Diagram of fuel cell and geometric arrangement for in situ Mossbauer measurements in the transmission mode/  

---

The states of Fe in Ir-Fe/Si02 catalyst have great effects on the catalytic performance in PROX reaction, and the promotional role of Fe is always associated with the presence of H2 in the reaction stream. By employment of quasi in situ Mossbauer spectroscopy, a clear picture, which shows the changes of different Fe species with increasing the H2 concentrations from 0 to 40%, is obtained. 

---