This paper deals with the morphology and surface chemistry of faceted voids existing in singlequasicrystalline icosahedral Al70.5Pd21.0Mn8.5. By observation with a scanning electron microscope of surfaces obtained by cleavage of the quasicrystal, the habit planes of the dodecahedral voids were identified. The chemical surface composition of the void surface was determined by Auger electron spectroscopy after cleavage in ultra-high vacuum.
The generation of Eu(III) precipitation and the Eu sorption on TiO2 particles in aqueous solution were studied using laser-induced breakdown spectroscopy (LIBS). The plasma emission intensity vs. the Eu concentration plot showed a good linearity in the concentration range of 6.6 × 10-3 M - 1.3 × 10-2 M for Eu aqueous solution at pH 1.1 and 6.6 × 10-5 M - 6.6 × 10-4 M for Eu2O3 suspension at pH 5.0. It was found that the generation of Eu precipitation was detected through a drastic increase of plasma emission intensity of Eu. The results suggested that LIBS is useful for analyzing the particles and the precipitation of Eu in aqueous solution, even if the Eu ion concentration is higher by orders of magnitude. Furthermore, we could measure the plasma emission of Eu ions sorbed on TiO2 particles under the conditions where the plasma emission of Eu ions could not be detected in the absence of TiO2. Hence, LIBS technique is considered to be useful to study the colloid generation of Eu.