News for hackers. Stuff that matters.

A comment on Engineers discover new class of materials that passively harvest water from air. Parent comment

Re:Engineers discover new class of materials that passively ... by robertclaus on Monday May 26, 2025 @04:51PM (#44101563)
While I generally agree that it sounds dubious, this argument depends on whether the entropy of the liquid in the pore is lower than the entropy of the vapor in the air in the pore. I could see a highly hydrophilic capillary restricting a vapor enough to where it has better entropy in a liquid state.

If that's true we just need to balance energy, which the cooler does.

[ Parent | on HN ]
Re:Engineers discover new class of materials that passively ... by mppm on Monday May 26, 2025 @05:57PM (#44102062)
> I could see a highly hydrophilic capillary restricting a vapor enough to where it has better entropy in a liquid state.

My other comment here (and and a reply to a similar question) has more detail [1], but in short: this is true for capillaries and pores, it is not true for "collectable" droplets on a flat surface.

1. https://news.ycombinator.com/item?id=44099078

[ Parent | on HN ]
Re:Engineers discover new class of materials that passively ... by ummonk on Monday May 26, 2025 @09:33PM (#44103184)
Replied to that comment as well but per the article they're not droplets on a flat surface, but rather droplets connected to pores by surface tension.
[ Parent | on HN ]