Competition between heterogeneous and homogeneous nucleation in a charged colloidal silica suspension

Throughout the past few years the problem of solidification of a melt via nucleation has been addressed in colloidal systems mainly suspended in a fluid, which are known to undergo crystallization and have received considerably interest outside the colloid community. Despite the great deal of work, the microscopic details of the crystallization process are still not completely understood. A very little is known about the influence of impurities or substrates on the kinetics of crystallization from the melt. Here as recently has been shown for homogeneous nucleation, colloidal systems can also help to get a deeper insight into the heterogeneous nucleation processes. We here present extended time resolved 2dimensional USAXS study of the solidification process in a flat cell.