Controlling the evaporation lifetimes of sessile droplets on superhydrophobic paper by simple stretching

Superhydrophobic paper was prepared by a soot template method. After being simply stretched at a strain of ∼7.2% under humid conditions, its high water repellency was maintained, but its wetting adhesion remarkably increased. The evaporation mode of a 5 μL droplet also transitioned from the constant contact angle (CCA) to the constant contact line (CCL) mode, which shortened the evaporation lifetime from ∼3560 s to ∼2380 s. This work shows significant advances for improving the analytical efficiency of lab-on-paper applications.