Orientation-dependent impurity partitioning of colloidal crystals

Publication date: 1 April 2016
Source:Journal of Crystal Growth, Volume 439
Author(s): Jun Nozawa, Satoshi Uda, Sumeng Hu, Kozo Fujiwara, Haruhiko Koizumi
Impurity partitioning during colloidal crystallization was investigated for grains with different orientations. Particles of various sizes were doped as impurities during the growth of colloidal polycrystals. The effective partition coefficient, keff, which is the impurity concentration in the solid (CS) divided by that in initial solution (CL), was measured for grains oriented in the [111] and [100] directions normal to the growth direction. The [111]-oriented grains were found to have a larger keff than [100]-oriented grains. This was analyzed by using the Thurmond and Struthers model. Though both [111]- and [100]-oriented grains were face centered cubic (fcc) structures, within several layers of crystals, the volume fraction of [111]-oriented grains was larger than that of [100]-oriented grains, yielding a larger driving force for nucleation, ΔGTr, and thus a larger equilibrium partition coefficient, k0, for [111]-oriented grains.



from #Ἀθηνᾶ via ola Kala on Inoreader http://ift.tt/1TZx7yq
via IFTTT