Facile fabrication of a superhydrophilic–superhydrophobic patterned surface by inkjet printing a sacrificial layer on a superhydrophilic surface

Based on the high wettability contrast, superhydrophilic–superhydrophobic patterned surfaces (SSPSs) have been used in a wide variety of applications, such as cell patterning, droplet transport and analyte enrichment. However, the fabricating approaches of SSPSs are commonly complicated and high-cost. Herein, a facile method was developed to fabricate SSPSs by inkjet printing a sacrificial layer on a superhydrophilic surface. The influence of a pinned three phase contact line on the depositing morphology of the inkjet droplet was investigated, and a uniform structure with high resolution was inkjet printed on the superhydrophilic substrate. Moreover, the patterns of the lines and films were directly inkjet printed on the superhydrophilic surface by regulating the inkjet droplet's coalescence. After modifying the surface by fluoro-alkyl silanes and removing the printed water-soluble deposit, the fabricated surface showed high wettability contrast between the printed area and unprinted area. Finally, the fabricated SSPSs were applied to achieve nanoparticle adhesion and droplet transport.