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- This is a drop of water, and I'm pretty sure I'm the first person in the world to have ever done this.

(upbeat music) Oh, that's amazing.

Oh my God, that's so cool.

I was wandering around on the internet and saw this.

These are small droplets of water that are coated in a very hydrophobic powder, polytetrafluoroethylene, also known as Teflon.

And these droplets behave like some sort of weird cross between solids and liquids.

They can roll like solid marbles.

They can even fall off a tiny little cliff.

Look at that cliff.

And they survive the impact.

They can roll across the surface of water, which is wild, but they can also divide and reform or engulf smaller particles like liquids can.

And if two of them meet under the right circumstances, they can merge.

And the two liquids inside can react, which we can see in this case by color change.

This is the paper these videos are from.

And a quick look through the references section leads to the paper in which these unholy solid liquid spawn things were first invented, back in 2001, which is surprisingly recent.

That's younger than me.

Liquid marbles, I gotta try this.

Liquid marbles are incredibly easy to make.

All you need is this $20 lycopodium powder, and then you just take some distilled water and put it on the powder and then shake it around a little bit.

That's it.

You've now got a liquid marble.

In fact, you've probably made a liquid marble yourself by accident.

If you've ever cooked with stainless steel, you know that a good first step is to get the pan hot enough so that when you put water in it, the water does this.

This is the Leidenfrost Effect, which happens when a liquid is sitting on something that is so hot relative to the liquid's boiling point that there is a continuously boiling part of the droplet that generates a super thin layer of gas between the drop and the pan.

Hence the whizzing around everywhere.

This is shot at 10% of normal speed.

And you can see here when I add a droplet of water to a spoon that is not hot enough, the entire droplet just sort of explodes.

It's actually pretty cool looking.

But then when the spoon's hot enough and I put a droplet of water on it, you can see that it bounces and then settles in to a Leidenfrost droplet.

You can see that the water droplet is stable.

It doesn't explode, and it also lasts way longer than it would if the spoon were colder.

Anyway, you can think of liquid marbles as Leidenfrost droplets, but at room temperature.

And instead of a thin layer of gas between the drop and the surface, there is a thin layer of tiny solid hydrophobic particles.

The same 2001 paper also mentions using very fine silica powder as a coating.

So I bought some of that too and tried it.

These liquid marbles seemed a little bit more robust than the lycopodium ones, but they were kind of hard to make because the powder is so incredibly light that water just sinks right through it to the bottom and refuses to do anything else.

Like this entire tub of the silica is just 100 grams.

If this were salt, it would be, I don't know, at least a kilogram.

As you can see, the silica liquid marbles are much more transparent than the lycopodium ones.

That's because the particles of silica are much smaller.

As particles get down to the tens of nanometers in diameter, they stop interacting with visible light.

So they just kind of disappear.

And you get these super cool, mostly transparent marbles.

One thing the paper mentioned is that you can actually float these marbles on water.

So I tried it.

And then I had the genius idea of rotating the beaker so the marble wouldn't just roll off the spout.

(George laughing) This time it actually worked.

Hey!

It really is amazing.

Whoa!

Oh my God, that's the coolest.

You can see the curvature of the water holding the marble up.

And if you pop a marble while it's sitting on water, you can see how even though the needle comes in from the top, the bottom of the marble appears to rupture first.

I don't know how that works.

And all the water becomes one.

And it was at this point that I started thinking, you know what?

I actually might be able to make a scientific discovery here.

I mean, the field is relatively new.

The materials are very cheap.

Liquid marbles are easy to make.

Like yeah, I could actually contribute to the sum total of human understanding.

And then I started reading the sum total of human understanding and 1,050 citations?

This is a highly cited paper, and just for comparison, the most cited paper ever in the history of all of science has only 300,000 citations.

So this is a third of a percent of that, which is high.

It's still very high.

And if you read some of the papers that cite this paper, people have done some amazing things with liquid marbles.

They've made magnetic liquid marbles that can open, accept new liquids, and close.

They've made magnetic marbles that open when exposed to UV lights, marbles from soot, marbles from liquid metal, marbles that function as gas sensors, micro reactors where the surface powder is also a catalyst as a bioreactor to make cellulose.

Transparent liquid marbles where you can watch an embryo develop.

That can be levitated, opened, and closed computer... (voices overlapping) Edible liquid marbles made out of silver dragees.

Is that even how you pronounce that?

Dragees?

Do you see all the buzzwords in this title?

Multi-stimuli-responsive liquid marbles stabilized by superhydrophobic luminescent carbon dots for miniature reactors.

What?

Liquid marbles went viral.

I didn't even notice.

And so the phrase in my head at this moment was stupendous arrogance.

Like, how could I have read this paper, thought, oh yeah, this is under 20 years old, I'm gonna definitely make a scientific discovery here.

I'll just schedule it for tomorrow.

What was I thinking?

Except I might have done it.

Back to my list of papers here.

One of the most fascinating ones is one in which the researchers made a liquid marble that could be reversibly opened and closed using a magnet.

They did that by starting with some iron chloride, hitting it with some ammonium hydroxide and a hydrophobic molecule, that gave them iron oxide nanoparticles bonded to the hydrophobic molecule.

And then taking those nanoparticles and using them to make liquid marbles.

And all the magnetic marbles papers I read basically used a version of this same synthetic process.

And that got me wondering, could I do this more simply, more cheaply, and in a way that hasn't ever been done before?

And I know that doesn't sound interesting or special, and I didn't think it would be, honestly, but it turned out to be both.

These are iron filings, and obviously they're magnetic.

They're mostly elemental iron, just Fe, that's it.

And as far as I can tell, nobody who makes magnetic liquid marbles uses these, but iron filings are much cheaper than making your own iron oxide.

You can see here that the particles are way larger than lycopodium or silica.

But remember that paper from earlier where scientists made a liquid marble from silver dragees?

Those are like a millimeter in diameter, so there is hope for iron filings.

Now the problem is elemental iron isn't hydrophobic at all.

What you're looking at here is a macro shot of iron filings, and I'm about to add some water on it.

And as you can see.

Ah!

The water just disappears.

I mean it completely wets the filings.

So I needed to make these iron filings hydrophobic.

And to do that, I had a dumb idea.

Teflon spray.

The original video that I saw used polytetrafluoroethylene particles to make liquid marbles.

That's Teflon, PTFE is basically Teflon.

And so I just googled the word spray after the word Teflon, and this came up.

Look, WD-40, it's not exactly WD-40, it's a weird cousin of WD-40.

And to get free shipping, I also bought this other Teflon spray which seems to be made for snowblowers?

Anyway, shockingly, the WD-40 seemed to turn the iron filings into a powder.

Wow, look at that.

So that's totally, this is before spraying, and this is after spraying.

It looks completely different now.

It looks much more like silica.

Where's the silica?

Here.

Looks much more like that texture-wise.

So I left this out to dry overnight, and then I made a liquid marble from it, and it didn't work at all.

Nothing happened.

So next, I tried the snow and ice spray, and it had the same effect on the iron.

And even more amazingly, it was so good at making liquid marbles.

This may actually be worth half a paper, like a paragraph.

It was just as easy as lycopodium, and it was way easier than silica actually.

And using these liquid marbles, I was able to reproduce the main finding of the magnetic liquid marble paper.

You start out with some yellow water in a liquid marble,.

You use a magnet to open that liquid marble.

You add some water dyed blue, and then boom, you've got green, proving that the two liquids mixed.

I had two thoughts here.

The first thought is I was shocked that this had worked.

And the second thought was, there's no way anyone else has ever done this before.

(laughs) Like I can already see the journal article title, facile production of magnetic liquid marbles using single step aerosol treatment at ambient temperature and pressure.

So why would two sprays that are both Teflon have such different effects on the iron?

And the answer is that neither one of them is Teflon.

Like look, even though the Amazon page for the WD-40 clearly says PTFE, which is why I bought it, WD-40's own SDS says that the active ingredient is quote, mineral oil, which last time I checked is not Teflon.

And as for the other spray, it turns out that it actually used to be made with Teflon as you can tell from this delightful YouTube marketing video.

- [Narrator] Snow sticks to your shovel.

DuPont Snow and Ice non-stick clear coating with Teflon Flora polymer.

- But if you look at the more modern marketing video and the can, you won't see Teflon anywhere.

Instead, you will see this weird BN logo with like a hexagon thing and ceramic blah blah technology.

I thought this was all just marketing babble, but it turns out that BN is a chemical formula, boron nitride, and it really is hexagonal.

Like way to go, DuPont marketing people on this one.

And of course, we don't understand why hexagonal boron nitride is hydrophobic.

There's even some controversy as to whether it is hydrophobic or whether it's just like surface impurities.

I'll let that play out in the literature.

Then totally unexpectedly, I discovered something else, which is that because we used iron filings rather than iron powder, the resulting liquid marbles were directional.

The shape of the marble depended on the orientation of the magnet.

When you open one of these liquid marbles with a magnet, there are actually two openings, one on top and the other on the bottom.

So you're actually not getting an opening, you're getting a cylinder.

And you can get really weird, interesting shapes by just tweaking the orientation of the magnet underneath the slide.

Yeah, like it's interesting, as you're moving it around.

Oh!

- There it goes.

(George laughing) - That was so wild.

So now I need to do a deeper dive into the literature, maybe do some more experiments, talk to somebody who knows all the recent research.

And if this does turn out to be a new discovery, my plan is to write it up and try and publish it in a journal.

And for that, I would like your help.

What I need are ideas for more experiments and links to papers that I may not have found that describe something similar to what I've done.

So if you want your name or your YouTube handle to be a co-author on a paper that will almost certainly be rejected from both "Science" and "Nature," but might make it into "Langmuir" and definitely will make it into "PLOS One," check out the description below, or just, you know, yell at me in the comments like you always do.