Precise crystal regulation and harvest by constructing confined flexible droplet crystallizer on 3D-printed sessile platform

Abstract Precise regulation of the mass-heat-momentum transfer carried great implications to the crystallization behavior in microscale droplet, which is one of the core concerns in crystal engineering. Herein, a confined flexible droplet crystallizer (CFDC) was facilely constructed on designed 3D-printed, matrix-type regular sessile platforms. Owing to the flexible morphology of CFDC, the synergized micro-flows generated by the integration of capillary flow and Marangoni flow in CFDC could be precisely controlled, which was validated from both experimental and simulative aspects. Standard cubic crystal was manufactured at the sessile platform center after evaporating an optimized CFDC (with 120° featured angle), where the synergized micro-flows created the perfect flow zone to balance the mass transfer and particle location. In addition, larger standard cubic crystal could be obtained via simply scale-up the platform (16 times) or supplementary feeding (secondary to forth feeding), manifesting great potential for high-quality crystal parallel preparation and harvest.