Kenneth O’Connor has worked with NASA Goddard engineers to develop a nanotextured coating with hydrophobic properties. The technology minimizes dust, liquid, and ice accumulation on its surface, similar to a leaf on the lotus plant. See below for details on a live webinar this month.

Kenneth O’Connor

NASA Tech Briefs: In what scenarios is this kind of dust removal required?

Kenneth O’Connor: The dust removal part of it is targeting mostly planetary or lunar missions. Dust presents a lot of problems for lunar missions. Lunar dust is very sharp – on the Apollo missions, we saw abrasive damage to the spacecraft and the astronauts’ suits. We also see an impact to the efficiency of solar panels.

NTB: How is the coating designed to remove the dust and the liquid?

O’Connor: Essentially we’ve created a nanotextured surface that has a really low surface energy. Dust sticks to a surface because of van der Waals forces. You’re just giving the dust particles less area to grab on to and also less surface energy to attach to.

NTB: How is the lotus-leaf nature of the design effective?

O’Connor: The reason that a lotus leaf is hydrophobic is for similar reasons. It’s a nano texture that also has a very low surface energy. The coating is modeled after that idea.

NTB: What were your biggest technical challenges when designing this?

O’Connor: We started out working with a university and the company nGimat Corporation. Initially, the coating required a 450 °C bakeout as one of the steps. One of the major challenges that we’ve already dealt with is getting [the coating] into a reasonable temperature application that can be sprayed, or dip- or spin-coated.

NTB: What is the coating designed to withstand?

O’Connor: We haven’t done a lot of environmental testing, but we know that it can [handle] 100 °C in vacuum for a duration. "Vacuum stable" means that the material doesn't degrade when exposed to a vacuum. This is important because we need the material properties. It is also important because we don't want to be a contamination source for the rest of the spacecraft that we are trying to protect. It isn't helpful if we keep a solar cell clean, but generate molecular contaminant in the process.

NTB: What kinds of applications do you envision for the technology?

O’Connor: Certainly, ground-based solar panel systems could benefit from a dust prevention system, because ground-based solar panel systems are sort of at the mercy of dust storms, with dust depositing on your surface.

There are a lot of places where the hydrophobic properties are valuable. If you could get [the coating] cheap enough and durable enough, it would be a great thing to put on your car, and you wouldn’t need windshield wipers. There’s also a need in industry for having temperature detectors that are underwater and may be susceptible to water damage. If you were able to coat those with a hydrophobic surface, then it would be protected. In industry, there are a lot more uses for water [removal]. For anything with corrosion, or anywhere that water is a problem for a process, it can be mitigated with a hydrophobic coating.

To learn more, read a full transcript, or listen to a downloadable podcast, visit www.techbriefs.com/podcast.


NASA Tech Briefs Magazine

This article first appeared in the September, 2015 issue of NASA Tech Briefs Magazine.

Read more articles from this issue here.

Read more articles from the archives here.