Hello!
I was wondering whether the time it takes for a water droplet to completely evaporate depends on it's support. In particular I would like to know if evaporation is faster on a hydrophobic (not super-hydrophobic) or a hydrophilic support. I could imagine that the surface area is larger on a hydrophobic support, thus evaporation should be faster. But I have no clue about this and would appreaciate any feedback!
All the best!
Phil
For sure we can say that evaporation and surface phenomena are interlinked (see Marangoni effect https://en.wikipedia.org/wiki/Marangoni_effect). There is an older paper on the issue, maybe it's helpful for you:
Article Effect of liquid-solid contact angle on droplet evaporation
For sure we can say that evaporation and surface phenomena are interlinked (see Marangoni effect https://en.wikipedia.org/wiki/Marangoni_effect). There is an older paper on the issue, maybe it's helpful for you:
Article Effect of liquid-solid contact angle on droplet evaporation
Thanks a lot! I read the article, it makes perfect sense and I will measure the evaporation time in my system (hydrophilic/phobic supports). Also, I did not know this journal exists! Funny title :)
As mentioned by Mr. Weippert, evaporation can matter and can have an influence. if the vapour pressure of your liquid is low (like with water or diiodo methane), the influence is negligible, for more volatile substances, evaporation prevention is definitely recommended. The Marangoni Effect also plays a significant role here,
You can estimate the evaporation rate by having a look at the volume of the droplet over time. Modern softwares for contact angle measurements track the droplet volume for each measurement and like this, you can see, how severe the influence of evaporation is in your case.
If evaporation is strong, it is recommended to create a saturated atmosphere. You could place your sample inside of a cuvette, fill the bottom of the cuvette with some of the liquid and cover the cuvette, so that you create such an atmosphere. Like this, evaporation effects can be minimized significantly and you should have good measurements
You are right, the evaporation rate is a also a direct linear function of the surface area (liquid- gas) of the drop (the solid-liquid interface does not contribute to evaporation), which is depending on the drop-surface interaction.
Do you by chance have a reference for this? If I understand the above article correctly, the solid-liquid interface has an impact.
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