Water Droplet Templating Technique to Design Three-Dimensionally Ordered Porous Structures of Polymer Film

O in MA is 8.1 wt %. By modulating the solution concentration (density) from 3% to 9% NC, the distribution of separated water droplets (pores) in the solution can be flexibly controlled from sinking to floating. On the other hand, substantial ordered honeycomb pores, originated from condensed water droplets, distribute uniformly on the surface of NC films. This water droplet templating technique can be extensively applied in various polymer films, providing an effective pathway to designing polymer films with a desirable porous structure and diverse functionalities.