Chemical vapor generation of silver for atomic absorption spectrometry with the multiatomizer: Radiotracer efficiency study and characterization of silver species
Abstract
Presented study follows the hypothesis that the "volatile" Ag species are actually metallic nanoparticles formed upon reduction in liquid phase and then released with good efficiency to the gaseous phase. Number/charge size distributions of dry aerosol were determined by Scanning Mobility Particle Sizer.
Ag was detected in 40-45 nm particles holding 10 times more charge if compared to Boltzmann equilibrium. At the same time, Ag was also present on 150 nm particles, the main size mode of the CVG generator.
The increase of Ag in standards was reflected by proportional increase in particle number/charge for 40-45 nm size particles only. Transmission electron microscopy revealed particles of 8 +/- 2 nm sampled from the gaseous phase, which were associated in isolated clusters of few to few tens of nanometres.
Ag presence in those particles was confirmed by Energy Dispersive X-ray Spectroscopy (EDS) analysis.