title: Behavior of pure gallium in water and various saline solutions.
abstract: This study investigated the chemical stability of pure gallium in water and saline solutions in order to obtain fundamental knowledge about the corrosion mechanism of gallium-based alloys. A pure gallium plate (99.999%) was suspended in 50 mL of deionized water, 0.01%, 0.1% or 1% NaCl solution at 24 +/- 2 degrees C for 1, 7, or 28 days. The amounts of gallium released into the solutions were determined by atomic absorption spectrophotometry. The surfaces of the specimens were examined after immersion by x-ray diffractometry (XRD) and x-ray photoelectron spectroscopy (XPS). In the solutions containing 0.1% or more NaCl, the release of gallium ions into the solution was lowered when compared to deionized water after 28-day immersion. Gallium oxide monohydroxide was found by XRD on the specimens immersed in deionized water after 28-day immersion. XPS indicated the formation of gallium oxide/hydroxide on the specimens immersed in water or 0.01% NaCl solution. The chemical stability of pure solid gallium was strongly affected by the presence of Cl- ions in the aqueous solution.
authors.affiliation: Department of Dental Technology, Matsumoto Dental College, Nagano, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Horasawa
authors.forename: H
authors.initials: H
authors.lastname: Nakajima
authors.forename: S
authors.initials: S
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Okabe
mesh_terms: D003722:Dental Alloys; D004577:Electron Probe Microanalysis; D005708:Gallium / Q000032:analysis / Q000737:chemistry*; D005709:Gallium Isotopes; D007101:Immersion; D012965:Sodium Chloride / Q000032:analysis / Q000737:chemistry*; D012996:Solutions; D013054:Spectrophotometry, Atomic; D013997:Time Factors; D014867:Water / Q000032:analysis / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003722:Dental Alloys; D005709:Gallium Isotopes; D012996:Solutions; D014867:Water; D012965:Sodium Chloride; D005708:Gallium