THE FORMATION OF BLISTERS ON THE PROBE SURFACE WHEN ATOMIZING LANTHANUM NITRATE IN THE GRAPHITE-FURNACE

The blisters (shells) and the reason for their formation on the surfac e of the graphite or tantalum probe during atomization of large amount s of lanthanum nitrate in the graphite furnace were investigated exper imentally using scanning electron microscopy (SEM), X-ray diffraction spectrometry (XRD), X-ray photoelectron spectroscopy (XPS) and Auger e lectron spectroscopy (AES). Blisters were observed on both the tantalu m and the graphite probe surface under suitable conditions. The bliste rs were not caused by carbon, but may be caused by lattice defects on the tantalum probe or through the formation of La(OH)3 owing to La2O3 absorbing water vapour on the graphite probe.