Effects of adjacent metals with different work functions

[FillBill]

Hi, someone was telling me that if you have two metals in close contact (like, one sputtered onto the other or something) with each other, if they have different work functions, you'll get some sort of diode effect (even without either of them being doped) if you have a current running from one to the other.

Does anyone have any information on this I could read about?

Thank you!

 

[Integral]

A useful device which uses this is the thermocouple. They are used for temperature measurement.

 

[Naty1]

Check WORK FUNCTION and CONDUCTION BAND
in Wikipedia for some background.

The photoelectric effect is also a work function phenomena...where absorption of a photon
releases a conduction electron.

I suspect any 'diode effect' depending on work functions of metals is miniscule...most metals tend to be pretty good conductors...SEMIconductor diodes use a p doping together with an n doping to create a p-n junction...which passes electrons in one direction far more than the opposite direction.