High-surface-area supported nickel-silicon alloys were prepared by treating Ni/Al2O3 with silane (SiH4) at 300-400°C in flowing hydrogen. Microbalance studies indicated that the supported nickel-silicon alloys were easily decomposed, compared with alloys prepared by bulk melting. However, the decomposed alloys were difficult to reduce, indicating formation of an interaction species. ESCA and ISS studies indicate that silane treatment brings about considerable shielding of the nickel surface which coincides with a drastic decrease in CO hydrogenation activity.
Toshiro Otowa, Marwan Houalla, David M. Hercules, Charles L. Kibby, and Leonidas Petrakis, "Surface Characterization and CO Hydrogenation Activity of Silane-Treated Nickel/Aluminas," Appl. Spectrosc. 43, 1082-1086 (1989)