Frost has long been a problem for human society. Norse mythology describes frost giants, also known as hrimthurs, as primitive beings who oppose the rule of Gods and create havoc and hassle. In modern society the effects of frosting can be equally dramatic: downed power lines, damaged crops, and stalled aircrafts. Moreover, frost and ice accumulation significantly decreases the performance of ships, wind turbines, and HVAC systems. Currently used active chemical, thermal, and mechanical methods of ice removal are time consuming and costly in operation. Therefore development of passive methods preventing frost and ice accretion is highly desirable. Our work in this area focuses on understanding the nano/microscale  mechanism of frost and ice accumulation on nanoengineered “anti-frost” and “anti-icing” superhydrophobic and lubricant impregnated surfaces.

Recently, we also developed an alternative anti-icing surface that responds to icing by releasing an antifreeze liquid that was stored within inner “dermis” layer hidden underneath a porous superhydrophobic “epidermis” layer. This type of two layer surface architecture was inspired by poison dart frog skin. The “on demand” antifreeze release mechanism is analogous to the way poison dart frogs release toxin from glands in their dermis through pores in their epidermis in response to sensed danger. By repelling water drops like normal superhydrophobic coating and releasing the antifreeze only in response to icing/frosting, our coating dramatically outperforms superhydrophobic and lubricant impregnated anti-icing surfaces, while reducing antifreeze use by 2 to 8-fold as compared to current industrial practices.