Interfacial microdroplet evaporative crystallization on 3D printed regular matrix platform.

Droplet evaporative crystallization on microscale heterogeneous surface is a vivid topic in chemical engineering, bioengineering, nanomaterials, and so on. Here, 3D printed interfacial matrix platform with regular pillar convexity and tunnel structure is fabricated to reveal the mechanism of the interfacial micro droplet crystallization. Element‐based rotation volume model is established to simulate the concentration and nucleation barrier distribution during the microscale process. Sodium urate monohydrate and NaCl crystallization on the pillar convex structure both confirm that confined capillary flow in the micro droplet and initial nucleation condition dominate the nucleation, growth control and particle distribution. Droplet crystallization stretches over the tunnel structure reveal an interesting phenomenon that two regions possessing distinct‐different nucleation barriers can isolated obtain the crystal particles from nanoscale to even millimeter scale. The fabricated platform and the capillary circulation transfer theory unfold a potential approach to harvest high value‐added crystals with specific morphology and desire sizes distribution. [ABSTRACT FROM AUTHOR]