Speaker
Description
Morphological control of crystals is utterly important in reticular chemistry, especially as a fundamental strategy toward preparing functional materials of superior properties. Despite the notable advancements in the realm of metal-organic frameworks (MOFs), where endeavors primarily focus on shape manipulation at the nano- and microscale during bulk synthesis and subsequent processing at the mesoscale (e.g., incorporation into polycrystalline films, patterns, and composites), a notable challenge persists in attaining a meticulous control over both the shape and size of macroscopic single crystals.
Here we successfully demonstrated the spatial and morphological control of crystal growth at the millimeter scale from a non-equilibrium state through the utilization of a microfluidic device. Specifically, we employed PDMS channels to confine CuGHG, a peptide-based MOF, where crystal formation occurred as a consequence of a diffusion-controlled supply of precursors within an advection-free microenvironment. Depending on the concentration of the feeding solution, continuous growth or shrinkage of the crystals was observed and recorded by time-lapse microscope. Our method not only introduces a novel approach for precisely shaping large-scale single crystals from metastable solutions but also draws attention to its intriguing resemblance to two fundamental morphogenesis strategies observed in biomineralization. The presented results, therefore, establish a fundamental basis for future studies in materials science, shedding light on how the size and shape of artificial crystals can intricately influence their properties and functions.Moreover, our findings provide a strategic avenue for tailoring the size and shape of peptide-based MOF single crystals to specific applications. This approach not only expands the horizons of crystal engineering but also opens up possibilities for the design and customization of materials with desired properties for various technological applications.
