Nanoparticle enhanced evaporation of liquids: A case study of silicone oil and water

Abstract

Evaporation is a fundamental physical phenomenon, of which many challenging questions remain unanswered. Enhanced evaporation of liquids in some occasions is of enormous practical significance. Here we report the enhanced evaporation of the nearly permanently stable silicone oil by dispersing with nanopariticles including CaTiO3, anatase and rutile TiO2. An evaporation rate as high as 1.33 mg/h·cm2 was measured in silicone oil when dispersed with 100 nm-sized CaTiO3 particles. Dependence of evaporation rate on the chemistry, size and structure of the particles suggests that some weak absorption sites on the particles half floating on the liquid surface are responsible for the facilitated evaporation of liquid molecules. Enhanced evaporation is also observed for water when dispersed with anatase TiO2 particles. The results can inspire the research of atomistic mechanism for nanoparticle enhanced evaporation and exploration of evaporation control techniques for treatment of oil pollution and restoration of dirty water

Heat transfer enhancement using air-atomized spray cooling with water–Al2O3 nanofluid

“…4 that the cooling time between 900 C and 200 C decreases from 4.8 s to 3.5 s by using alumina nanofluids, with and without presence of a surfactant. This is due to enhanced evaporation of water spray by nanoparticles, has also been found earlier by Zhang et al [40] for the case of water when dispersed with anatase TiO 2 particles.…”

Solar steam generation by heat localization

“…The other important characteristic of the DLS is its hydrophilicity, which promotes fluid flow to the surface. The capillary force in the exfoliated graphite layer enhances the evaporation rate of the fluid through several mechanisms: formation of thin films on the surface of graphite sheets 21 , enhanced surface area for evaporation 22 and formation of three-phase contact lines at the edges of the capillaries 23,24 . The graphite structure has hydrophobic surfaces as evidenced by the contact angle ( Supplementary Fig.…”

Nanoparticle-mediated evaporation at liquid–vapor interfaces

“…Some pioneering literature reports the addition of nanoparticles to bulk solvents can either enhance or suppress evaporate rate depending on the surface chemistry, size, and structure of the particles. [25][26][27] Other studies show the evaporation of sessile droplets with dispersed nanoparticles in the bulk is enhanced due to the synergistic effect of increased initial spreading, prolonged contact line pinning during evaporation, and greater thermal conduction for phase change. [28,29] Cheng and Grest [23] reported weak blockage effect of nanoparticles on evaporation when nanoparticles assemble into crystalline structures below the liquid-vapor interface.…”