Wettability of clean metal surfaces

Experimental and theoretical investigations bearing on the question of the wettability, by water, of clean oxygen-free metal surfaces are reviewed. Results on gold, silver, and copper are discussed in terms of surface cleanliness, surface structure, and extent of dispersion (London) force interaction. It is concluded that clean solid metal surfaces are hydrophilic. They will yield a zero degree contact angle when prepared in the amorphous state and possibly in the perfect crystalline state as well. These results do not necessarily preclude the possibility that physical interaction at the metal-water interface consists solely of dispersion forces.