Surface-functionalized metal foil and method of preparing the same

A method of preparing a surface-functionalized metal foil, the method comprising:

• preparing a surface-modified metal substrate using a first surface modifier;
• preparing surface-modified metal nanoparticles using a second surface modifier;
• immersing the surface-modified metal substrate in a dispersion containing the surface-modified metal nanoparticles to adsorb the surface-modified metal nanoparticles as a single layer on the surface-modified metal substrate;
• and
• drying the surface-modified metal substrate on which the surface-modified metal nanoparticles are adsorbed and performing light firing of the surface-modified metal nanoparticles to form a surface functional layer, the light firing including:
• forming an alloy containing at least one element of the surface-modified metal substrate in the surface-modified metal nanoparticles,
• forming an alloy containing at least one element of the surface-modified metal nanoparticles in the surface-modified metal substrate, and
• the at least one element of the surface-modified metal nanoparticles being diffused into the surface-modified metal substrate as a whole and forming a metal alloy containing the at least one element of the surface-modified metal nanoparticles,
• wherein the second surface modifier is a polymer having one or more selected from the group consisting of a carboxyl group, an amine group, an imine group, a hydroxyl group, and a carbonyl group.