Photochemical vapor generation of Zinc and Gallium

Abstract

Photochemical vapor generation (PVG) of Zinc (Zn) and Gallium (Ga) was firstly reported in this study. The main parameters influencing PVG of Zn and Ga were investigated with inductively coupled plasma mass spectrometry (ICP-MS), such as the type and concentration of low molecular weight organic acids (LMWOAs), the concentration of transition metal ions and their synergistic effects, the wavelength and time of UV irradiation, and pH of sample solution. Formic acid (FA) and Cu2+ were required for the generation of volatile species of Zn and Ga. In addition, the effects of interfering ions on the PVG of Zn and Ga were investigated. Good precisions with 2.3% and 2.7% were obtained under the selected conditions for replicate measurement of 200 ng mL−1 Zn and Ga standard solution (n = 7), respectively. The limits of detection (LOD, 3σ, n = 11) were calculated to be 8.8 ng mL−1 and 0.77 ng mL−1 for Zn and Ga with PVG-ICP-MS measurement, respectively. Carbonyl compounds were speculated to be formed in this study. Moreover, nanoparticles containing Cu, Zn or Ga were found in liquid solution after UV irradiation, which may be useful for investigating the formation of natural nanoparticles in environment as well as the isotope fractionation of Zn and Ga in photochemical processes.