  We report on an investigation of spin-polarized secondary electron emission
from the chemically inert system: graphene/Ni(111). An ordered passivated
graphene layer (monolayer of graphite, MG) was formed on Ni(111) surface via
cracking of propylene gas. The spin-polarization of the secondary electrons
obtained from this system upon photoemission is only slightly lower than the
one from the clean Ni surface, but does not change upon large oxygen exposure.
These results suggest to use such passivated Ni(111) surface as a source of
spin-polarized electrons stable against adsorption of reactive gases.
