Breath figure patterns prepared by spraying ultrasonic atomized water droplets

Abstract

Honeycomb-structured porous films have widely potential applications in chemical sensors, tissue engineering, micro reactors, catalysis and so forth. An enhanced breath figure method with spraying ultrasonic atomized water droplets replacing the water vapor in humidity is proposed to fabricate multi-level and large-area breath figure patterns (BFPs). Well-defined polyphenylene oxide honeycomb films were prepared at a proper spraying time. The pore size and the regularity of the hexagonal arrays could be regulated by changing solution concentration. Especially, honeycomb films with two-level pores were fabricated by spraying atomized water droplets two times. Moreover, large-area BFPs with film area larger than 100 cm2 could be formed on the glass substrate. The large-area BFPs formation capability of the enhanced BFM in this work give new insight into more widely application in surface engineering. For example, slippery surfaces were prepared using the large-area BFPs as the holding structures. And the prepared slippery surfaces showed extremely low critical sliding angles for water, and also demonstrated efficient self-cleaning property.