Liquid marbles as thermally robust droplets: coating-assisted Leidenfrost-like effect

TL;DR

Liquid marbles, coated with microparticles, can sustain a Leidenfrost-like effect at any superheated temperature, providing thermally robust droplets that do not require a specific transition temperature.

Contribution

This study demonstrates that liquid marbles can exhibit a Leidenfrost-like effect across a wide temperature range, unlike traditional droplets that need a transitional temperature.

Findings

Liquid marbles can withstand temperatures up to 465°C without transition.

Microparticle coating enables levitation and insulation of the liquid core.

The phenomenon is due to microparticle-assisted levitation and insulation.

Abstract

The Leidenfrost effect-prolonged evaporation of droplets on a superheated surface-happens only when the surface temperature is above a certain transitional value. Here, we show that specially engineered droplets - liquid marbles - can exhibit similar effect at any superheated temperatures (up to 465 oC tested in our experiment) without a transition. Very possibly, this phenomenon is due to the fact that liquid marbles are droplets coated with microparticles and these microparticles help levitate the liquid core and maintain an insulation layer between the liquid and the superheated surface.