Real-time dissolution of calcite crystals

We propose a study on the dissolution of nano-sized calcium carbonate (calcite) crystals in aqueous solution to elucidate the role of the 3D interface (i.e., flat facets versus edges and corners) on its chemical reactivity. Thus, we will perform an in-situ and real-time investigation based on speckle Bragg coherent diffraction imaging (spBCDI), a novel approach that we are developing. Sp-BCDI is based on modulating the coherent beam wavefront with a phase plate to produce a strongly non-uniform, “speckled” illumination, that efficiently samples the 3D diffracted intensity around a Bragg peak. This reduces the data acquisition time (down to a few seconds) and enables the imaging of dynamically evolving crystals. We expect to observe the crystal morphology at various stages of dissolution. Exploiting the sensitivity of spBCDI to crystalline distortions we will correlate strain fields and defects to the morphological evolution of the corners and edges during the dissolution.