Dissolution-recrystallization process

The addition of polyelectrolytes with strong inhibition ability [241,242] will stabilize amorphous nanobuilding blocks in the early stage and then stimulate a mesoscale transformation [40] or act as a material depot in a dissolution-recrystallization process. This could be shown in a time resolved study on the CaCOa scale inhibition efficiency of polycarboxylates, where amorphous precursor particles were detected in the initial stages [243]. 

Li3P04, whose presence was detected using XRD, would then dissolve and recrystallize to LiFePOa where it would collect on the edges of the pre-existing LiFePOa nanoplates. Thus, is can be surmised that dumbbell LiFeP04 mesocrystal formation is based on a dissolution-recrystallization process with eventually complete phase transformation. 

These two modes are both strong functions of the electrochemical potential and the operating temperatures. Platinum particle growth can occur through Ostwald ripening in a simple surface diffusion process or through a dissolution/recrystallization process (Ross 1987). Platinum dissolution concomitant with an irreversible loss of the active metal... 

Control over the size of particles depends upon the mechanism of particle formation. From a broad viewpoint, there are two fundamental mechanisms of particle formation. These are (a) in-situ transformation of a virtually insoluble precursor to the ultimately stable phase, and (b) dissolution of any solid precursor materials followed by recrystallization from solution to the ultimate phase (21). For particles synthesized by in-situ transformation, the driving force is the difference in free energy between the solid precursor and the final product, similar to any solid-state transformation. In contrast, it has been proposed that the difference in solubility between a sparingly soluble precursor and the final product is the effective supersaturation, or driving force for the formation of particles in a dissolution-recrystallization process (21). Classical notions of precipitation fall into the latter class of dissolution-recrystallization. 

For operating the secondary growth, the seeded support is hydrothermally treated in a diluted synthesis mixture (with or without template) to grow the seed crystals, resulting in a compact zeolite film. A simple steaming of the seed layer can also partially consolidate the zeolite membrane by local dissolution and recrystallization processes in the seed layer. The films are finally dried or calcined if an SDA was used. 

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