Maybe by means of Electrostatic Force Microscopy (EFM)?

Normally, a metal surface should not support an isolated surface charge density. The relaxation / dissipation would essentially be instantaneous.

Can you explain when and how you think that a metal surface will have a surface charge that can be measured quantitatively?

Hi,

Metals can stand surface states in which an electron is attractively bound to the surface by its electrostatic image in the bulk of the metal. Inverse photo-emission spectroscopy is the way to measure these states.

For definition you could consult:

http://en.wikipedia.org/wiki/Surface_states#Surface_states_in_metals

http://en.wikipedia.org/wiki/Inverse_photoemission_spectroscopy

Following is a list of relevant publications in the field:

http://scholar.google.fr/scholar?hl=fr&as_sdt=0,5&q=surface+states

RKI instruments among many others proposes photo-emission instruments.

@C Hirlimann: Yes ... of image charges I am aware. The starting question made no such distinction. I am still curious whether this is what was meant or not.

Yes Jeffrey, I am not sure I answered the exact question. But it doesn't hurt other readers to know about surface states, right?

Thank you for all the readers

certainly, Dr. Jeffrey, I would like to clarify your doubt..........

I am thinking when a metal has its native oxides (OR) when it is coated by an oxide or hydroxide rich layer the surface may have charge.

in general we say metals contain positively charged when it is immersed into water/solution and thereby the formation of double layer enriched with the oppositely signed ions at the surface.

therefore I am interested to know is it possible for me to tailor my surface charge of the metal either to +ve/-Ve by surface modification technique. If it is possible how to quantify this?