Fig. 3: Durability of liquid repellency for the nanofilament-coated membrane.
From: A super liquid-repellent hierarchical porous membrane for enhanced membrane distillation
a Receding contact angle \({\theta }_{{{{{{\rm{r}}}}}}}^{{{{{{\rm{app}}}}}}}\) and b contact angle hysteresis \({\theta }_{{{{{{\rm{CAH}}}}}}}\) of water on the PE, PTFE and nanofilament-coated PES membranes as a function of immersion time in Milli-Q water at 80 °C. Error bars indicate standard deviation (n = 6). c Selected snapshots showing the contact angles of a 5 µl water droplet on PE-0.2, PTFE-0.2, and NF-PES-8 membranes before and after 7-day immersion test. The images and contact angle measurements were obtained by using micro-goniometer (DataPhysics OCA35). Snapshots comparing the mobility of dyed water droplets before and after immersion test on (d) NF-PES-8 membrane (motion blur due to fast drop movement) and (e) PE-0.2 membrane.
