A unique metal-semiconductor interface and resultant electron transfer   phenomenon
  An unusual electron transfer phenomenon has been identified from an n-type semiconductor to Schottky metal particles, the result of a unique metal semiconductor interface that results when the metal particles are grown from the semiconductor substrate. The unique interface acts as a one-way (rectifying) open gateway and was first identified in reduced rutile polycrystalline titanium dioxide (an n-type semiconductor) to Group VIII (noble) metal particles. The interface significantly affects the Schottky barrier height resulting in electron transfer to the metal particles from the reduced rutile titanium dioxide (TiO2) based on their respective work functions. The result is a negative charge on the metal particles which is of sufficient magnitude and duration to provide cathodic protection of the metal particles from surface oxidation. 
S. L. Taft
cond-mat.mtrl-sci