Spectroscopic evidence for a gold-coloured metallic water solution

Area of Science:

• Materials Science
• Physical Chemistry
• Condensed Matter Physics

Background:

• High pressure can theoretically metallize insulating materials like water, but pressures required are experimentally unattainable.
• Water under accessible laboratory pressures exhibits superionic properties, not metallic conductivity.
• Metallic solutions of solvated electrons in ammonia are known, but water's reactivity limits electron doping.

Purpose of the Study:

• To investigate the possibility of creating a metallic water solution through electron doping.
• To overcome the challenges posed by the explosive reaction between alkali metals and water.
• To characterize the properties of this novel metallic water solution.

Main Methods:

• Adsorbing water vapor onto liquid sodium-potassium alloy drops in a vacuum.
• Suppressing the explosive alkali metal-water reaction at low pressures (10^-4 mbar).
• Utilizing optical reflection and synchrotron X-ray photoelectron spectroscopy for characterization.

Main Results:

• A transient, gold-colored layer of metallic water solution was successfully formed.
• The solution was heavily doped with approximately 5 x 10^21 electrons per cubic centimeter.
• Experimental evidence confirmed the metallic nature of the electron-doped water solution.

Conclusions:

• Metallic water solutions can be prepared by controlled electron doping, circumventing extreme pressure requirements.
• The developed method effectively suppresses the explosive water-alkali metal reaction.
• This research opens new avenues for studying the properties and potential applications of metallic aqueous systems.