Thumbnail image of graphical abstract

Honeycomb-structured porous films have important applications in numerous fields, such as optoelectronic devices, tissue engineering, and micro reactors. The breathe figure method (BFM) has received much attention as a highly efficient, low cost technique to prepare honeycomb films. Pengfei Zhang, Huawei Chen, and Deyuan Zhang describe an improved BFM to fabricate well-defined porous films by spraying atomized micro water droplets. Pore size and distribution can be well controlled by tuning process variables including spraying time, spraying flux, and solution concentration. Multi-level honeycomb film formation is made possible by spraying atomized water droplets twice. The cover shows a SEM image of polymer films with uniform pores formed by this method. DOI: 10.1002/app.41163